Will a disc brake setup off a 1996 trans am fit a 1972 chevelle spindles and all?
Anyone try it

Not a bolt-in for sure. Search this forum for Tall spindles or b-body spindles for some different choices that can be made to work.

A 1996 F body is a strut front-end. There is no way the spindles could be made to work out massive amounts of one off fabrication work. Not even close to being worth the effort. Is it an LS version car? If so then the calipers and brackets can be made to work without too much hassle. Do a search for LS1 brake conversions or C5 brake conversions. The 2 are almost identical.