There are two 3 speed overdrive transmissions that fit Chevy cars and trucks. Both of them use a Borg-Warner OD unit. The Muncie SM-319 has 4 bolts holding the side cover to the transmission case, and the Saginaw transmission has a 7 bolt cover. The Saginaw is an extremely scarce item. Both traqnsmissions require a push/pull cable to lock out the OD when trailer towing or descending long hills. There is also a control relay and a kickdown switch in the throttle linkage that should be scavenged from the donor vehicle.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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