6 and 8 cyl transmissions in that era are the same. The OD case has a boss cast into the left side and is drilled for the shift rail, otherwise it is the same. Some of the early standard transmissions also had the boss but was not drilled. Truck transmissions have the lower holes threaded where they mount to the bellhousing, cars do not. 62 up versions have a shorter tailshaft, but the internal gears are the same. Not sure where to find the P/Ns. I get parts from Anaheim Gear in Anaheim, CA. I mostly get seals and bearings from them for rebuilds but they have hard parts also. They are quite pricy on the hard parts. I find these transmissions at swap meets really cheap and harvest the good stuff.
Fred

Last edited by rfs56trk; 03/25/2012 4:54 PM.

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