New guy in forums and R/C world too, and as normal from a beginner I come with some questions, but first some background about the project.
As title say I got a M1A2 Abrams from Hobby Engine, I find it a fun an very cheap (price) tank and love it, but I find it to be a bit slow in general and I'm not a fan of plastic tracks, so I was getting the idea after watching a YouTube video, to upgrade my tank in a small way, but got no idea if it will work.
First get a new set of gearbox with metal gears, was thinking to use Henglong 3869/3879/3888/3899
In said video, this guy used a Tiger I metal tracks and, but they will work? If yes, this would be good?
Mato Metal upgraded Tracks, sprockets, idler wheels parts set for Heng Long 3818-1
For turret traverse also noted it can go 360 degrees and painfully slow, this is solved with a new unit?
Also I leave link for the video that gave the idea to try this:
I know some guys will go for the "Buy a better tank" way, but here in Mexico city are a bit expensive and rare to find, a Tamiya 1/16 King Tiger is over 900dlls and you still need to buy a controller for it, sorry for the long post and thanks in advance!
Also I got another question, this time about batteries, I play airsoft and moved long ago from NIMH to LiPo batteries, so I got the idea to change the stock battery (7.2v 800mAh) to a 8.4v 1100mAh, but when I looked at both batteries something was wrong, stock one got the polarity inverted compared with the airsoft one, pics for reference:

Extra voltage will damage something?
And when looking in tank's insides the question continued, black wire is really ground? If yes I only need to invert the tamiya connector in tank to use the new battery, right?
