How Do You Mount Caliper On Front? Or Back?

The only reason there is a different part number is; the 73-75s use a 2.6" bore caliper piston, the 76+ a 2.75 (or so) caliper piston. Physically, either will bolt to the rear or front. Sway bar interference is an issue in 65-72 LCA A bodies when using the stock length, LONG end links. If you convert to the shorter 3" links, there is no caliper / sway bar interference.