I Planning on swaping out the factory 4 piston set- up currently on the Demon in favor of a single piston set up I took off of a 73 Dart sport. Reason for this is I have SBP on the front and LBP aftermarket axles on the rear. Are the front spindles the same? Also curious if I use the same factory upper control arms as well. Will the brake proportioning still be the same? Thanks.