Ok, I think I'll go ahead and buy the s2 set from RS tomorrow after school. My current xmod is being a pain in the ass. I think the differential is really messed up in it because when I had the body off and floored the xmod the left tire would just spin and spin and the right tire would just sit still. I even applied pressure to the car to see if it would catch but it didn't. It's also got some stripped out screws above the rear end assembly now. I'm just gonna return it, 1 wheel drive isn't very fun to drive because it can't take turns very easily and is hella hard to control. After I return my xmod and get another, I'll buy the s2 kit and then go over to walmart and get a $4 spin brush and fiddle with that. If I'm not happy with my results then I'll break down and buy a reliable pinion puller (one that wont break on the first pinion) and an orion motor. Until then, later!