The problem with the rear rotors is that the parking brake friction surface is inside the rotor hub. The disc caliper has no function with the P brake as most modern rear disc cars do. You cannot replace the rear rotor with a hat and disc combo and keep the P brake. To do that you would need a new caliper and now you need a new mount and now you have to completely redesign the whole mess. Or call Dr Diff/Cass and use one of his kits.

Oops, Bob J, I think I misinterpreted your post. I thought you were saying that you could use everything Chrysler and just replace the discs with something else.