These are the things you will need. 1-Scalextric Porsche,1-Slot-it 25,000 Motor (assuming you have a Professor Motor controller, otherwise stay with the stock motor and gear), 11 tooth gear, Phillips screw driver, super glue, 1-Fly rectangular magnet, a solder gun, and a gear press.  Silicone tire are preferred.
	First, take the body off the chassis. Second, take the round magnet and place it in the front position and add a dab of super glue. Then remove the motor and rear axle.  Take the Fly magnet and place it in the rear pan of the car under the rear axle with a dab of super glue. Now use your soldering gun to remove the motor from the lead wires.  I'll explain why in the next step.
	Now you will need to remove the lead wire from the Slot-it motor and solder the Scalextric wires back on. The reason we chose to do this is because of the ease of the terminals for the contacts.  Now you can use this motor to plug into other Scalextric sidewinder cars.
	Now take your gear press and press on the 11 tooth brass gear. (I have since tried a 10 tooth gear. Wow!! This gives great low end speed)  Then once you have the gear in place, take a Dremel tool and trim off the excess shaft on both sides (optional).
	Now carefully place the motor and rear axle back in place.  Finally, put the the body back on and enjoy.