New motor adivse

[rcjmaxx]

I have a project that I'm working on and would like some advice on a motor for it. It is a 15lb monster truck that has a 1st generation Emaxx tranny. This is to be a basher not racing or top speed runner, so 40 mph is fine. I have a 52t spur and tons of 5mm pinions so a 5mm shaft is prefered. I'm not sure if the Maxx tranny and motor plate will limit me or not. I was thinking 1521, but will that diameter fit my Maxx motor plate? Will the motor mounting holes lineup? Should I keep waiting for the Medusa 80mm motor? Any suggestions welcome.