The cable is totally unnecessary for OD operation. Some people lock them into the overdrive position with a short piece of welding rod bolted from the lockout lever to the transmission housing. The planetary unit locks itself out automatically when reverse is selected, as anyone who has ever been inside the B-W overdrive unit knows. The only purpose for the cable is to lock out the OD when you need compression braking, like on a long downgrade. There is a lockout pin that is moved by the internal shift linkage when reverse is selected. The only difference between the SM-318 case and the 319 case used with the OD unit is one hole drilled in the case for the lockout pin. I have converted several standard 3 speed transmission cases to OD by drilling that hole.
I strongly suggest you listen to people who have hands-on experience, not just a good internet search engine.
PM me for a good electrical diagram to make your OD work like the factory intended it should.
Jerry
