To function as designed, a BW overdrive trans needs a cable-operated lock out installed, a kick down switch on the throttle linkage, a relay, and some wiring. The OEM relays and kick down are a little scarce, but the function can be duplicated with a Bosch-style relay and a micro switch with a little tinkering to fabricate a mounting bracket for the switch. Don't get persuaded to try to substitute a toggle switch for the right wiring- - - -it's very simple to make it work right. The wiring setup would be the same for either the Saginaw of the Muncie transmissions. If you have a choice, try to get a Saginaw. That synchronized 1st. gear is very handy, even if you have to modify the shift linkage a little to use it. I can provide a wiring diagram for the Bosch relay and micro switch if you find a transmission to buy.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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