im looking to swap the rear end off an 85 Trans am which has the borg warner rear end with disc brakes to a 1988 firebird that had a 10 bolt drum setup. the master cylinder looks to be brand new on the 88. ( I got the 1988 car about a year ago and havent gone over it 100% due to the cold winter days) Can i just swap the porp valve from the 85 to 88 and still use the 88 master cylinder or do i need to use the 85 master cylinder?