Also, if you can find a way to do it, add a heatsink or two to the driver for the large motors by using mica insulators and thermal paste to mount finned heatsinks to the mosfets, either individually or all on the same heatsink with mica insulators so they don't short to the heatsink. It will make it run cooler. Fans are also a good option, blowing cool air across the Mosfets. (24V fans running off the motor power so the faster the motor goes the faster the fan goes . (cool , huh ?)