[Jason in TX]

Not to throw a wrench in the works, but I just wanted to bring up another overdrive option.

With the adaptor from Klings, you can put a 36-39 transmission behind your A that has synchromesh for around $600-800. No more grinding gears. Then behind that put a Volvo overdrive spliced into the torque tube for $1500. This combination is almost $1000 cheaper and does not require cutting the frame.

With the Ford OD, you are limited to 4 gears. With a non overdrive transmission and an overdrive in the torque tube, you actually have 6 gears since you can shift 1st, 1st with overdrive, 2nd, 2nd with overdrive, 3rd and 3rd with overdrive. When climbing a hill last week following a convoy of Model As driving 25 miles an hour, I was really happy to have 2nd with overdrive. It was less than 3rd gear, but stronger than 2nd. The car didn't lug but also stayed at low RPM. Just another thought.