I can say that a hacker c50 motor and a plett maxximum will fit the flm tranny case, gearing choices will be different as the motor will not get as close to the spur gear. Both of those motors are larger than 40mm and appear to be the same diameter or slightly larger than a c can feigao.
It should fit, they are not as big as a plett, and the plett motor had a slight interference fit with the lower plate. I ran 32p jato spurs (58t?) and a 15t pinion and it meshed up fine with the plett.
Now you may have issues with the diff internals holding up, but that is another story...
thats all upgraded already, i was running a 6l but my buddy wanted it and I have this 8xl just sitting here, i figure it should turn a big pinion so that should be fun
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It's "Dr. _paralyzed_" actually. Not like with a PhD, but Doctor like in Dr. Pepper.