I'm doing a body-off restomod on a 1982 vette. I have finished working on the chassis and started putting the body back on. I was careful in documenting the number of shims on all 8 mounts. I purchased and installed a polyurethane body mount kit with the correct number of shims on all mounts. After placing the body back and inspecting the mounts, I see a gap of approximately 1/4" on both rear #4 mounts. My question is: should I take some shims off of mounts 2 and 3 or should I just add some 3 mounts each to the #4's; or am I doing something wrong here. Please let me know what you think. Thank you

 

Are you sure the body is not resting on something it should not be resting on ?

Have you got the other mount 'pucks' on the right way ? , from memory there's a big and a small "puck" .

have a look at the car from the side , there should only be a small area of the frame showing under the sill panel

 

I just recently did all the body mounts on my 77. I posted a fair number of posts on the project in the "What have you done to your corvette today" thread in the general forum.
Anyway, I did it one side at a time in a tiny one car garage. When I set down the first side. (Drivers side) I had a gap at number 4 about an inch. On my car from factory I found no shims at all on number 1 and 2. And 2 shims on both 3 and 4. I couldn't remove any at number 2. I also found the replacement shims where thinner than the originals. So I went with total thickness rather than count.
at any rate. I left it sit without tightening anything and rear bumper mount completely undone. After 24 hours I had a 1/4 inch gap. The body seemed to "rest" into place. Door gaps looked good and doors opened and closed perfectly. But still that gap. I then raised the passengers side and did those mounts. Once again matching shims by thickness rather than count.
basically 3 of the new ones matched up to 2 of the originals.
when I set down the right side I had a 1/2 inch gap at number 4. Drivers side was now down tight.
I just started bolts for 2 and 3. Checked alignment with the alignment holes in the sill plates through the frame. And let it sit. 24 hours later I couldn't see a gap but could just wiggle the shims. Let it sit another 24 hours. Everything was tight.
I tightened down bolts starting with 1 and 2 on both sides. Then number 3 on both sides. Then number 4's. Then the rear bumper mount bolts and shims.
hope this helps. Seems these body's can flex a fair amount when we lift them. Give it time to relax back into place. Mine did. No cracks and doors and windows are all aligned perfectly.

 

Thank you for the advise... I made sure that I placed the correct number of shims everywhere and the car is not tilted. The pucks are also in the right order. I'll follow your advice and let it sit for a day then I'll start tightening it at increments. Maybe that will do it. Thank you.

 

While it settles...keep a close watch on the door gaps at the jambs/quarter panels...
IF the gaps begin to WIDEN you may want to shim the #4s until the gaps are normal again.

 

Funny that. Even when I first set down my body. My door gaps looked great. Even with the large gap at the number 4 mount. And as it settled down. I didn't see any noticeable changes. Mind you I didn't measure with a micrometer. But nothing noticeable. And if you shim to much at the number 4 mount. You'll never get the rear bumper mount bolts back in.

 

Well...I just checked the gap in the #4 mounts and it looks like it did settled down a bit but there's still a gap. I think the gap will fit three shims. The gap on the doors are not moving at all. Should i just fill the gap with shims or should I take some shims off the #2's and #3"s?

 

Take a look in the back where the rear bumper mount bolts go in. Will they line up? If yes see if you can just start one or two on each side. If so I would put maybe 2 shims in not 3. As you start tightening from the front keep watching those gaps. As you get the number 3's tight you will see 4 come down a tad more. If you put in to many shims at 4 the top gap at the rear of the door will close up.
if it's a no to those bumper bolts lining up. Maybe wait another day. Don't force it.

 

I want to thank all of you for your help. I followed your advises and left the car sit for 48 hours to allow the new body mounts contract. After fighting a bit with the #3 mounts to make them line up, I was able to tighten everything up and the #4 mounts were good. No more gaps. The door gaps were also good. Now that I started to work on the inside electrical, I noticed that my driver door is a bit lower than before. That gaps are good but I can tell it's lower when I try to close it. Is this caused by the new mounts? or is the body misaligned? Please let me know what you guys think I should do. Thx

 

Is it sitting lower at the top where it meets the quarter panel?

 

Nope... The door itself is a bit lower than the quarter panel
.

 

I'm sorry, I didn't fully understand the question. The door is siting lower on the top . That's how I noticed it.

 

Adjusting the door hinges might cause big headaches making the gap change for the worse.
When the door is open can you lift the door slightly at the rear where the door latch is because of slack in the door hinge pins?
IF SO... you may be able to loosen the striker and raise it enough to raise the top-rear of the door until it's flush with the top of the quarter panel.

If you DO raise and retighten the striker.........
Just be careful and close the door S L O W L Y to make sure the gap is not too small causing the paint to chip on the rear edge of the door.