I have 57 Chevy that I installed a Napco setup in. It originally had 3.90 gears, but since one ring & pinion set was chipped, I replaced both axles with 3.38 gears from Patricks (very helpful & he gave me a discount on the seccond set since I ordered both at once). I have a 3spd overdrive trans installed. So far so good, but I really haven't driven it much since I'm re-doing the body. Some people suggest that 3.38 gears with a the 3spd overdrive is way too tall for a rock climbing NAPCO. My logic is that I won't be doing any rock climbing and I don't have to put it in overdrive unless I want to (e.g., highway cruising). In any case, I'll find out how it works, but it seems to me that if you're not worried about extreme off-road conditions the set-up should be reasonable. I have a modified 261 in it now, I've decided to go to a 283 V8 sometime soon, so that may help mitigate the gearing even more. As they say, it's my truck, my time & my money; I'll make it the way I want it.
