Allison Transmission for my V12

[Bob Korves]

For display and fun purposes with a light vehicle a hydrostatic transmission might make more sense. It would allow for easier locating the components in the chassis, no shafts needed. Could easily be all wheel drive. Such a setup might be difficult to find at hobbyist prices.
http://www.wisegeek.com/what-is-a-hydrostatic-transmission.htm#didyouknowout