I would suggest RC-Monster, you can get the motor mount, servo plate, and battery tray. It is all high quality stuff, and the RC-Monster forum is one of the most helpful and knowledgeable group of people when it comes to 1/8 electric.

Mount: http://www.rc-monster.com/proddetail...=RCMmugenmount

Battery tray: http://www.rc-monster.com/proddetail...MFPbatterytray

Mod 1.0 pinions: http://www.rc-monster.com/proddetail...=5mmmod1pinion