OK, the OD switch I am referring to is the torque converter lockup, so if you can adapt the current three speed lockup control that's fine, but it's beyond my ability. For that reason I am using the hydraulic switch with a modified 700R4 and an Edelbrock 1406 carb (600 CFM) on a non-electronic '76 Corvette 350 block. I don't want to mess with the electronic controls either, but if your 350 has them it may be easier to simulate the original setup than to eliminate them? Still you seem to know pretty much what to do now. Best Wishes.

Don Shillady
Retired Scientist/teen rodder