quark placement/neu/ direction?

first things first, you people are awesome, i've had very little headaches while building my g2r e-revo (also my first build). Although, it has taken some time to complete, it is still a fun build. With all the great and speedy advice, i have become hooked on this hobby. so I can't thank yall enough.
austin

ok now back to my nearly finished build. I'm soldering up the trakpower 4900;s and the neu/quark combo. i need to decide the direction of my tranny, motor, and diffs. i will be racing mostly, so track performance is key.

1. solder connectors on quark/neu. yay or nay? if so male on which?

2. which tranny/motor direction has best weight distribution? cog?