Brushless (new) e-revo questions?

[truckbuilder06]

I have a couple of questions to ask. I have the new e-revo and it is converted to brushless it has Feigao 8xl motor with the MM esc and I'm going to use 2 2s2p 8000mah packs wired to get 14.8v.

Question #1. I used BrianG's calculator for gearing, but will a 22t pinion and 58 spur keep the temps at a reasonable level? If not any suggestions.

Question #2. I have mounted the feigao 8xl to the traxxas single motor mount using the heatsink that has different mounting options. I'm using RC monsters heatsink with end clamp on the motor, My issue is that i had to turn the pinion gear around (so grub screw is towards end of motor shaft) to get the pinion and the spur to line up. Has anyone had this issue as well. I couldn't turn the pinion the other way because then i could not tighten the grub screw for the pinion. I'm using the mod .8 gears

Question #3. Later I would like to upgrade the motor to a neu 1515 model motor will I need to get a different esc(have MM right now) or can I get by with what I have?

Thanks to anyone that can help....