The easiest thing to do is find an A999 and use that. 100% bolt in. It's not an OD transmission, but is a 904 with a lockup converter. It will drop the RPM by 200-400 RPM on the road. You seem to want the least possible work and that's it.
I have done some research on the A999 and it may be an option, although the goal is to drop highway RPMs around 1000, from 3300-3500 to 2300-2500. Thanks Rusty!
