[ChuckDickerson]

For some reason I think having two separate gearboxes (in this case Dewalts) connected by chains such that both gearboxes are driving all three wheels may be a bad idea all together. What happens if one of the gearboxes goes bang? Unless the gearbox fails in such a way as to allow "free wheeling" the second gearbox would then be trying to drive a more than likely jammed gearbox and would itself be more than likely to go bang.