[mrnoble]

Both last year's and this year's kitbot gearboxes were designed to work with two CIM motors per box, so you could run a 4-CIM drivetrain. It is irrelevant that they are different from each other. Mounting a second motor to each gearbox only requires that you attach the proper pinion gear (with key), and insert it into the space that's already there for it in the gearbox. Screw the new motor into place, then add two more motor controllers to your wiring and electronics setup.