[jerry56]

This first shot is the basic frame of a WPL 4X4 I narrowed the tires to make the duals and modified the front tray to fit the motor.
This is a stock gear reduction motor from WPL....a little on the slow side and not a lot of torque. The frame is the stock WPL these ain't so great...sturdy enough for me to start with but the rails themselves are to narrow....after I figure out the basics I will probably go back and rebuild this one
The axles are the metal upgrade and seem pretty good but really I have no idea how they will hold up, only time will tell.
The linear actuator is a servo city 33rpm gear motor with a 1/4 Black and Decker masonry bit ($2.97) from Walmart I cut it down with a dremel. It will tip a 5lbs weight so it seems to work pretty good the bit moves the slide one inch per revolution so it moves pretty quick.