I'm installing a '79 Firebird rear end in my '54 'Burb. Do I put the original springs above or below the new axle? And, if I reverse the springs, will that help me center the axle with the fender opening? This project will have a 300hp 350V8 tied to a 700R4 and the '79 Firebird rear end is a 2.73 posi; the front subframe is also '79 Firebird. It has a '69 Impala factory A/C system, with a 2" lowered dash to accommodate the vents and A/C controls. But I'm up in the air about axle over/under the springs. Anyone's help will be greatly appreciated.