This is one of those mods requiring patience, help from a good friend, and adult beverages to numb the pain. While it does help out in the looks department, replacing the grille and surrounding trim on an older Chevy truck is an incredible pain in the ass and you've really got to be broke, a masochist, or a glutton for punishment to even attempt it by yourself. Whether you're using aftermarket or OEM parts, putting the jigsaw puzzle of pieces together and aligning everything is a real chore.
I previously swapped a front...
I previously swapped a front clip pulled from an '84 GMC Suburban onto my '73 C10. The sheetmetal was in decent shape, but all of the grille mounting tabs were busted and the trim was dented.
I bought my '73 Chevy C10 knowing full well that there was bad bodywork and dents galore lurking beneath the rattle-can primer job. In fact, I knew I'd be swapping the front clip even before I handed over the cash to buy the truck. Ironically, updating the old front end to newer sheetmetal was actually easier than replacing the grille trim, even though the new clip didn't bolt on and required some fabrication. I'm not saying you shouldn't do the same to your truck, I'm just warning you that this job will take the better half of a day to complete, and at some point you'll want to huck a breaker bar through the windshield of your truck.
I ordered the parts for my truck from LMC Truck and found quality parts once I ripped open the cardboard boxes. The chrome-plated bumper arrived via UPS unscathed and the grille trim fit nicely for reproduction parts. Now, if only GM had come up with a better method of securing the grille trim to the truck, I'd be a happy man. Check it out.
 Before 1.On the way to my...  Before
1.On the way to my buddy Tim's house, the grille practically fell out of the truck. Once the truck was at his house, we pulled the front end apart so we could paint the top of the core support and engine compartment. We degreased the metal using acetone and brake cleaner, and then used Scotch Brite pads to scuff the sheetmetal in preparation for the spray can black paint. | 
After
|  2.Next, we used a ratchet...  2.Next, we used a ratchet and a -inch open end wrench to unbolt the stock bumper brackets from the frame horns. |
 |  3.The old parts looked so...  3.The old parts looked so bad that once they were out, the truck actually looked better naked. |  4.Here is where the fun starts....  4.Here is where the fun starts. The grille surround is held on by a series of metal clips, which have 10mm nuts thread onto posts that extend through the core support. The best way to access them is from the rear of the core support, which means the radiator comes out along with the bumper, grille and headlight bezels. In fact, the job is even easier if you unbolt the headlights too. |
Tech Tip
Lighting The Way
You've got options when it comes to parking lamps. LMC has a kit to swap the stock ones into locations behind the new grille, or you can purchase rectangle variations which go into the backside of the bumper. We went with the bumper lights. Here's a look at the procedure for swapping the lamps to the new grille though. The old lamp housings are held onto the old grille via a pair of inch nuts and two clips.
 |  1.After removing the nuts,...  1.After removing the nuts, we simply cut off the clip mounting locations on the other side of the housings using a drill and cut-off wheel. |  2.The old housings are transferred...  2.The old housings are transferred to the rear of the new grille. LMC provides hardware to secure the housings using Phillips head screws and washers. |
 1a.LMC provides new clips,...  1a.LMC provides new clips, which are slid into the channel on the back side of the new trim pieces. The trim and clips are then lined up with the holes in the core support and the nuts are tightened onto the clips. Sounds easy, right? Well it's not. The clips tend to fall out of the trim as you try to put the trim on the truck. You'll also need to have a friend who's got nothing better to do on a Saturday to hold the trim in place while you fumble with the small nuts behind the core support. Eventually, you'll get the nuts on and then realize that the trim needs some persuasion to line all the pieces up. | 
1b. |  2.There are five clips on...  2.There are five clips on the top and bottom edges of the trim and two more on the sides. It's a tight fit getting a -inch drive ratchet to access some of the clips. |
 3.After a few hours of fighting...  3.After a few hours of fighting the trim to get it locked into place, we gave up without getting it to line up completely. By this point, we were so happy that the parts were on the truck and not falling off, that our judgment was impaired and we thought this was the greatest sight we'd ever seen. Lining up the parts from LMC is totally doable with enough time and help though. We just didn't have the patience to fight the truck and the hardware any longer. |  4.LMC's replacement grille...  4.LMC's replacement grille was a welcome addition to the truck. It looks like billet, but it's actually plastic. Not only is it easy to assemble, but it fit the truck perfectly. It's held in place by six -inch hex head screws along the top and bottom edges. |  5a.The new headlight surrounds...  5a.The new headlight surrounds were another quality piece. They lined up easily and were held in place with four Phillips head screws. This completes the grille install on the truck. Now on to the new bumper. |
5b. |  6.We simply transferred the...  6.We simply transferred the old mounting brackets to our new bumper. You'll notice that there are parking lamps in the bumper now that once resided in the old GMC grille. | |
Tech Tip
The Sheetmetal Swap
If you're curious about swapping a late-model front end onto your early model square-body truck, you should know that the parts won't simply bolt on. You'll need the core support from the new truck and that will allow you to bolt up the fenders. However, the hood hinges are in different locations on the trucks. Our '73's hinges pivoted from the middle of the inner fenders. The hood hinges on our '84 front end pivoted from the firewall. This required modifying our firewall. The framehorns on the later-model trucks are also shorter, so our '73 framehorns required trimming and new holes to be drilled in order to swap bumpers. Check it out:
 1.That faint block line represents...  1.That faint block line represents the amount of material I had to cut off my '73 model frame horns. I also had to drill a new bolt hole in the top of each frame horn to re-attach the bumper bracket. |  2.To relocate the late-model...  2.To relocate the late-model hood hinges to the firewall, we used the foam hinge seals as templates in order to determine the hinge location. Notice that the rear of the hinge is where the mounting bolts are supposed to go. Our '73 is missing the sheetmetal in this area to bolt the hinge to. We'll deal with that right after we clearance the firewall for the hinges. |  3.We planned on using an air-powered...  3.We planned on using an air-powered reciprocating saw to cut the slots for the hinge arms. To make the each end of the slots cleaner looking, we drilled pilot holes and used them as a guide for cutting out the sheetmetal. |
 |  4.Next, we cleaned the paint...  4.Next, we cleaned the paint off the side of the firewall and MIG welded 1/8-inch-thick steel to it as a base for the hinges. |  5.Then, we drilled a pair...  5.Then, we drilled a pair of holes for the hinge bolts and welded nuts to the bottom of the metal bases so that we wouldn't need to stuff a wrench behind the metal to bolt the hinges in place. This was helpful because although we thought we had the hinges in the perfect spot, once we bolted the hood in place we realized we needed to move the hinges around slightly to get the gap between the hood and fenders perfect. |
 |  6.Note that the top of the...  6.Note that the top of the hinges have a pair of clips that are used to bolt the late-model cowl in place. The older trucks didn't have a separate cowl. The hood of our '73 extended all the way to the windshield. Moving the hinges to the firewall gave us at least two points to secure the new cowl to the cab. The center mounts on the new cowl are just hanging around over the vents for the time being. | |
The Final Word
As difficult as it was to install our new grille trim, the end result is worth the effort. When combined with a new grille, bumper, and lighting, the frontend of my C10 looks less like a derelict pickup, and more like a sport truck. Stay tuned because we'll chronical the rejuvenation process of this truck in upcoming issues of ST.