I would like some feedback +/- about the fairey overdrive. I will be attending the FJ45 run this fall. The drive will consist of 1800 miles round trip. I have the original 3 speed in my LPB with a PTO. I also have in my possesion a fairey overdrive for the 3 speed. So my conundrum is this. Choice A: Do I install the overdrive onto the 3 speed thus giving me a better final drive ratio. Choice B: Swap in a HF55 5 speed and be done with it?