[SgtMillhouse648]

Haven't been able to watch the vid (dialup), but as for rear wheel steer, 648 did a 3 wheel tricycle drive for 3 years and it worked very nicely. The two front drive wheels were powered by the FP's, and the 3rd was built on a crab module kindof approach driven by a CIM and turned with one of the window motors. It could turn a full +-90, and the programmers programmed in an electronic differential to keep the wheels from slipping. As for driving it, we used a homeade steering wheel made out of one of the wheelchair wheels on a pot. Where the steering wheel pointed, the independent wheel rotated, and a joystick was used for purely throttle. It was an awesome setup, but we ended up ditching it for crab steer last year, and this year, I think we perfected it.....
Malhon