Are 57&58 floor pans the same for 62 Series coupes and sedans?
I am reasonably certain that the floor pan is the same but the sedan floor fixed B pillar makes a mess of the rear pan which is probably the one you are trying to replace.
Even I can't say for sure. The X frame was redesigned for '58 to accommodate either coil or air springs. The rear frame is way different and the trunk pan is substantially larger for '58. The outriggers in the rear frame are a bit different.
I've read that the '58 coupe, Sixty Special, Sedan de Ville and extended deck 62 series sedans have the largest trunks ever made. I do know a '58 coupe trunk is a lot flatter and wider than my '57.
I have to repair passenger front and both rear pans. I've heard the repop pans out there are pretty different from the original pans. I'd like to get original rust free pans out of a parts car and it would substantially increase my options if I could use pans from 4 door cars as well. Luckily my trunk floor is in great shape and doesn't require any work.
Basically, the '57 floor pan is the same for a coupe and sedan. Obviously, there are some differences at the B pillar; if this zone is OK on your project, you may go ahead. The largest difficulty is to find a sedan floor which is not rusted...
By the way, I used for my '56 Biarritz elements from a '56 Sedan de Ville. I had to fabricate some bits, but overall this was a good alternative.
With the exception of the trunk floor, as noted by Walter Youshock, the body shell for '57 and '58 is the same,; maybe the passenger floors are identical, but I frankly don't know.
The reproduction floors for Cadillac are useless.
Great, thank you! The rust is confined to the foot wells so using parts from a sedan floor shouldn't be a problem then.
On an unrelated note, are 57 and 58 front fender wheel well lip moldings the same?
They are not, this is a different part number.
Thanks Roger.
Roger is right on the parts being different. I have both and if you put them next to each other you can see the design change.