Hi---I just measured the S10 rearend. It is 53 3/4" from axle flange to axle flange. When I pulled the wheels off SURPRISE---damn thing has no brake drums on it. Now, assuming that the brake drums are say---1/2" thick each, that makes it 54 3/4" face to face of drums, where the wheels set up against. For some reason, the auto wreckers around Barrie, Ontario seem mentally challenged, and I am having a hard time getting plain steel 15" wheels to mount on this rearend. I have checked carefully, with a Vernier micrometer, and an S10 rearend has a 5 bolt pattern, on a
4 3/4" bolt circle. The studs appear to be 12 millimeter diameter, (approximately 0.472"). Hope this helps.

I am building a 1931 roadster pick-up, and the dimension from side to side of the box, where my fenders mount, is 43", and the fenders are 11" wide from the mounting surface(against the box) to the inside of the outer edge of the fender. I think that dimension should be the same for a roadster, I"m not sure about coupes.