When I needed to replace the clutch in my '57, I wanted the original style Borg & Beck (pressure spring) and not the diaphragm style. The Borg & Beck is for heavier applications and has a little heavier peddle than the diaphragm type and is the correct clutch for my 2 ton. I researched the specs on it and started looking around at the different auto parts sites, I found that the same specs also were called for in the '57 Belair with V8 engines, bought the clutch kit at Autozone for $100 and it fit like a glove, been using the truck for 10 years as a truck with zero issues.

1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy