yeah as far as im aware they fit any gas engine nad i should imagon there a good mod as it would allow you to gear it for good accleration and then 2nd gear can be a gear for a good top end so you get the best of both worlds, i may be wrong in sayin this though as im a learning newbee to these trucks, as far as reverse i aint seen any on line yet and since i got my truck that all i been doin is search for upgrades and info,