GMC grill alignment issues

[87Skier]

Hello,

I finally got tired of my top grill molding missing a bunch of chrome, so I decided to replace it and clean up the rest of my grill parts.

I'm installing them and ran into some issues. I know some are common but I don't really know where to go from here.

First, the hood is too close to the bulkhead, but I have no more adjustment on one side. I'll probably just file out the holes in the mount until I get the necessary adjustment.

Second, there is about 3/4" to 1" gap between the hood and top molding.

Third, the gap between hood and grill is not square (larger gap on passenger than driver side).

Fourth, there is virtually no gap between the top molding and the eyebrow trim on the right hand side but a 1/2" gap on the driver side. The grill and top molding are snug fit between fenders and the eyebrow trim fits the same on either side.

Fifth, the attachment points near the headlights that connect the main grill to top molding do not align. If I attach these, the top molding doesn't align with the eyebrow trim on either side. I don't care if these get used or not. They weren't used in the old piece.

I also looked at the rest of panel gaps near the door and cowl, there's nothing to indicate another alignment issue that might need to resolved before this. If I can't figure out anything for this it's something i can live with.

[thomasrepair]

I just built a 68 GMC with new grille and a new top painted upper grille(both aftermarket). It was a pain!!! luckily i test fitted those before painting, Its not plug and play. I used my die grinder on a couple holes. Long bolts going into the fenders helped get bolts started. I used new cab mounts and new mounts on the core support. I found that I needed to get creative to shim the core support to frame mounts. Most of the parts i assembled on the grille, fenders and cab itself had never seen each other. so i had no reference as to how well they lined up before.
I guess my point is that there are lots of mounting points from the cab forward that have an effect on that grille. Its a process.
I would definitely check all your rubber mounting points to start.
Good luck.

[Corts60]

Look up member Hatzie. He has a lot of manuals on these trucks. He may have a manual that describes the alignment process.

[87Skier]

Originally Posted by thomasrepair

I just built a 68 GMC with new grille and a new top painted upper grille(both aftermarket). It was a pain!!! luckily i test fitted those before painting, Its not plug and play. I used my die grinder on a couple holes. Long bolts going into the fenders helped get bolts started. I used new cab mounts and new mounts on the core support. I found that I needed to get creative to shim the core support to frame mounts. Most of the parts i assembled on the grille, fenders and cab itself had never seen each other. so i had no reference as to how well they lined up before.
I guess my point is that there are lots of mounting points from the cab forward that have an effect on that grille. Its a process.
I would definitely check all your rubber mounting points to start.
Good luck.

Good advice. My rubber mounts are definitely shot, but I am waiting to replace those until just before I fix the cab rust, even if it means some misalignment of the grill.

I'm considering putting a slight bend on the top edge of original grill so it fits the top molding nicer. I think this will solve 2 of problems, leaving the hood alignment and top molding side to side difference issues.

I am going to remove the battery tray and charcoal canister for easier access. The nuts on the eyebrow trim at a pain to get to with everything in place.

Originally Posted by Corts60

Look up member Hatzie. He has a lot of manuals on these trucks. He may have a manual that describes the alignment process.

I'll look him up. Thanks

[rechinca]

You really need to start with the basics of cab and rad supports. You will not get anything done other than enlarging holes that doesn’t fix the issue. I just put my front end back together after removing almost everything but the cab, bed and rear axle. I put in new cab mounts, takes about an hour, and still took over an hour to get my gaps halfway right. It’s a lot of snugging but not tightening a lot of the bolts to keep moving. That includes radiator support to fenders and the fender braces as well as the radiator support mounts. Moving one has the equal effect on the opposite side. Sometimes you have to work with the point 180* from your problem to fix it.

[87Skier]

Originally Posted by rechinca

You really need to start with the basics of cab and rad supports. You will not get anything done other than enlarging holes that doesn’t fix the issue. I just put my front end back together after removing almost everything but the cab, bed and rear axle. I put in new cab mounts, takes about an hour, and still took over an hour to get my gaps halfway right. It’s a lot of snugging but not tightening a lot of the bolts to keep moving. That includes radiator support to fenders and the fender braces as well as the radiator support mounts. Moving one has the equal effect on the opposite side. Sometimes you have to work with the point 180* from your problem to fix it.

I have a Jimmy, so to start with the basics I would need to replace all the rubber mounts, replace the missing rocker boxes, and fix the rust in the rocker panels and floor sections to eliminate bulkhead flex. I do have the room, nor the time right now to tackle these jobs.

The only holes I'm going to enlarge are for the hood hinge spring assembly. I'm at the end of my travel, yet the hood fouls on the cowl. The cowl, doors, and fenders have decent gaps. Most of the gap issues are just 70's build quality, and aren't misaligned.

[rechinca]

87 that totally makes sense given the info. One of the hood tricks I learned as a kid was the tilting down just the back of the hinge. If you haven’t done that yet, it produces a lot of down the road changes. I aligned from the cowl forward. Even just those little 1/8” moves make HUGE changes. I had someone doing the pushing on panels as I checked gaps and tightened/loosened bolts. I had too close at the back of hood and rr/lf rubbing and the opposite on the opposing corners. Just loosened the majority of bolts and especially the radiator core support. Good luck as setting the gaps to look good in the quality of build these had is a challenge!