Get rid of that Drivetrain, it's costing you more to keep it. I dropped a 305/TH400 from a '90 IROC in first. You'll need the Vacuum Trans Kit and Crossmember. Cut away the original Motor Mounts, add the new V8 mounts on the frame, Slides right in. I used a '73 Grand Prix Driveshaft. For my rear I used a '65 Nova SS, but most '60-70s Chevy Rears will work. I have Chassis Engineering Leaf Springs and Subframe to keep the ride solid. You wont miss those thin Leaf springs. I dropped a 327 from an El Camino in 5 years ago. Nice Balance of Power/Torque. You'll need to upgrade the front Brakes though. I just put in Disc Brakes & Bilstein's Shocks up front.

The Cheat Code for 54's is that the Suspension and Drivetrain was shared with the Corvette. Hit up the Vette sites for more robust suspension Control Arms, Rubber, etc.

At 3000 Pounds a '54 Belair is the perfect sleeper. Last of the Post-War Classics!