I have what I suspect to be a '77-'78 front disc brake set-up on a '72 E-body that (I think) originally had front drums. The only problem I can see so far is that the upper ball joint has a slightly larger diameter than the hole in the top of the front spindle. Question is: If I machine the spindle to fit the upper ball joint can I get this set-up to work?

If it were newer b body stuff the upper ball joint should be the same. They aren't four piston calipers are they? Could be early a body stuff which is expensive to get parts for. But for the question if there is enough material there and the spindles are the same dimensions, it probably could be done.

If it is the whole set up from the newer car you need to change the spindles to a 73-76 a body disc spindle. Measure the spindles you have now according to this tech archive and that will tell you if is wrong. Also check out the part numbers if you can see them.

http://www.arengineering.com/articles/brakesmuscle.html
http://www.moparaction.com/Tech/archive/disc-main.html

Thanks for the info., I'll take a closer look at the parts for part numbers. I have the standard calipers (not dual piston). The reason I think the front spindles/brakes are later B-body is because of the front brake hoses, I brought in an old hose to the local auto parts store and they found a match with the later B-body stuff (the hose attachment point to the caliper is a block with a hollow bolt as opposed to the hose with a threaded fitting that the '72 E-body should have). This set-up was already assembled when I got the car. Doesn't seem to be any issues with the rotor on the spindle. Only issue I can see is the previously mentioned fitment between the ball joint/spindle. I'll be taking a closer look at this as well.

**edit: ok, after reading through the links above, it looks like the previous owner installed the later B-body set-up on the car without changing out the spindles**