After building an overdrive unit made like a brownie,running it a long time,trading it off a guy found it and came to my garage wanting it put in a ton ford truck. I told him no.1 too light for 1-ton...no.2 truck geared too high already,he insisted so put the O.D.in his truck. Forgot about electronic ignition,when I got to wiring ended up using an ice-cube relay it worked but was high geared . Now he might have learned to gear it a little differently but finally tied onto a disc frozen to the ground twisted the input shaft off. Years later told me about it had retired so just gave me the unit. It's laying dead out there in the shop.