I find Cars www.oldbuickparts.com has the best cushions part BM644A. Fusick olds had the best mounts. Tell them it is for a Buick and you need two extra for the firewall. Throw their cushions and bolts in the trash. AMK has the best bolts.
I am using poly bushings. Looking for the added stiffness to go along with my frame mods. Also found out that the #5 bushing (from the front) which is usually just set in place can be bolted in. There is a caged bolt in the body.
I finally tackled the rusty bolts for the core support mount/cushions on my wife 69 Skylark convertible. I noticed the heavy rust and deterioration when I replaced the battery tray. The right side bolt was removed after cutting the head off with a die grinder. The left side broke which made removal easy. The bolts are 7/16-14 x 3 1/2or 3 3/8 with a 11/16 head. InLine tube has the correct grade 8 bolt 7/16-14x 3 3/8 with 11/16 head (no flange) INL14637. I used an AMK washer #B-13021 ,which is exactly like the original, under the nut. What I need to do is determine the size of the mount and cushion. Fusicik mounts are 2 1/2" in dia. and SS396's are 2". InLine tube's are also 2". Has anybody replaced just the core support mount plus cushion and knows the correct size? Top bolt in photo is right side. Thanks
Would it be possible to change from the doors back...? the ones under the doors on mine are pretty much in bad shape, would just like to change those only?...for now..... My car is complete and running, so taking the front end apart is not a option for me. can you post some pics of the finish work if you have any.....
All depends. If the bolts come out without messing anything up probably. Good luck on just that. There may be enough flex in the frame to lift the back of the body up enough to get the back 4. The ones under the seat I don't know.