[olddog]

I have a TKO600 with the .64 OD in my car. I don't like the huge step between 4th and 5th. It is like having a 6 speed with 5th gear removed. I would much rather have the .82 ratio 5th gear. If that isn't tall enough then change the rear end ratio.

I think you should try to find someone with this transmission and drive or ride in it before you pull the trigger. Changing the 5th gear ratio is quite expensive, as the hole shaft has to be replaced, so once you buy it your stuck with it.

Hope that helps.