Fisher price for the drivetrain?

[Teched3]

Just to add another thought or two. Remember, you may be running on carpet at times on the perimeter, and the F/P motors do not like to be stalled. If you do use them, make sure you provide venting paths where you mount the motors. If you don't they will overheat quickly with no air movement even if they aren't stalled. Take a close look at the F/P gearboxes the motors are mounted on to see where the vents are located and sized. That is if you use different gearboxes.