It's good to know what year/model transmission you have but that is not necessarily going to determine what clutch you need. It could possibly have a 10" or 11" clutch depending on which flywheel it has. The only way to get the correct clutch is to remove it and match it up or have it rebuilt.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine