I have a 2wd version in my 57 Vette and ran one in my son's 68 Camaro.
I think the transmissions were only used through 87, not 88. If you go to car-part.com and search for a 83 silverado - manual transmission - 4 speed, it will be identified as "with side shifter". The top shifters were the cast iron granny gear transmissions. If I remember correctly the iron trans have a unique bolt pattern for where the trans bolts to the bell housing. make sure you get the bell housing. The gear ratios are similar to a 700R4, with a .73 OD for 4th gear.
We used a cast iron trans in the camaro that was converted to 2wd prior to us getting it, or, maybe it was always 2wd. The bell housing was hard to track down.
This is my spare MY6/ A833 transmission. 2wd uses a TH350 yolk. The 2wd trans is the same length as a TH350 short tailshaft, or a M20/M21 transmission.
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