I made an electric R/C power wheels & used a [link=http://www2.towerhobbies.com/cgi-bin/WTI0001P?&I=LXN600]7075MGJ[/link] to steer. It works but I plan on cleaning up the steering a little & hopefully working out a more reliable servo arm. I stripped the 1st one & quickley found out that a servo saver springs way before the wheels turn even when the truck is moving. I'm also working on a 4wd (maybe 6wd if the 4 wheeler I got a month ago works) truck that will still have a in car control so my neighbor's son can play around.

Plan on doing something for traction. The plastic wheels spin like they're on oil if you try to go uphill. An engine will provide some weight but you might still have to add a few pounds. I used coffee cans full of nails in the bed of the truck but it still wasn't enough. Stretching a piece of an inner tube over the rear wheels helped on pavement but did little on grass.

My parent's neighbors were used to me running R/Cs when I lived there but the BigFoot got several repeat glances when they realized there wasn't a kid in it.