I know there was a thread somewhere around here where a guy put an MMM in a silicone oil bath in a sealed box in his Summit. Might want to look around for that, I'm pretty sure it worked out and the oil dissipated the heat (but did void warranty). Probably would be a mess if you ever had to take it out of there, but just brainstorming here. Then you could focus the water cooling on the motor.
How do those pumps I linked compare to the others you've found so far?
nitro temp gauges would be a relatively easy way to keep an eye on what you are actually accomplishing. just wrap the loop around the heatsink or the can or servo or whatever.
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It's "Dr. _paralyzed_" actually. Not like with a PhD, but Doctor like in Dr. Pepper.