If that's your plan, you could also take your existing rear rotors to a machine shop and have the OD turned down by 1/4". Even 1/8" might be enough. Will the main calipers and pads be OK with a 1/4" smaller OD rotor?
That being said, it seems like a lot of work when you could simply grind some material off of the parking brake calipers. It would accomplish the same thing and eliminate the need to disassemble the rear uprights to remove the rotors.