I just got a mmm2 i have up graded spur to 65 tooth and pinion to a 14t. I am getting 2 new Max Amp 6500 MAh 2s 150 cell LiPos. I have already upgraded front A-Arms will do back soon, and all pushrods. What other upgrades should i get? P.S. I would like to have a REALLY TOUGH Summit!!!!!!