Yep, i just got a MMM V3 last week. Im running 5s, same as in the vid, im not THAT crazy

. My MGM is limited upto 6s anyway. No worries on the ratio, ill work it out now, just didn't know which diffs you were running (RCM buggy or truggy

) Gotta remember the gmaxx single speed ratio is 1.7777, but with the CD its 1:1, i've also got buggy ratio diffs, so the spur/pinion will be kinda weird. No need for the gears, i don't think they'd fit between the frame rails, ive got a 48/10 combo to try out. I'll crunch some numbers right now, but i think theres something wrong with Brians calc, theres a Neu 1515/3D, but no Neu 1515/3D (polished) option

.
The necks real good now, im back to running, riding, gyming again. I just got cleared to get back into all this stuff a week ago, also back at work which is good, i need more money for RC

Unfortunately i cant get back into a race car for another 3 months, need to wait for the muscles/nerves to regenerate, (they take alot longer than bone.) So hopefully by March everything is all good.
have a good sleep
EDIT: thanks to BrianG's calc, heres what i got...
Shauns final drive ratio: 16.04537:1
My 42/16 final drive ratio: 8.68269:1
My 48/10 final drive ratio: 15.87692:1
My 46/12 final drive ratio: 12.67949:1
Now i know why my MGM burnt...