That guy did an amazing job. I may have to bail out of what I am doing and try to use his design. I’m trying to make the motorized sleigh to be a single unit using this motor and battery pack combo
http://www.bricklink.com/catalogItem.asp?S=5114-1
http://www.bricklink.com/catalogItem.asp?S=5038-1
which are both 20 year old designs. The “power function” motor in the video appears to be much stronger and does not require any gearing up, I’ve had to build in at least three steps up to convert the high speed low power motor output to a more powerful low-speed motion.