
I'm not trying to make you spend money...I'm trying to spare you potential disappointment and save a neat little time capsule of an RC10. Foam core chassis weren't sturdy even when they were new. They were a "failed experiment" that sacrificed strength to save weight. An aluminum tub with a stealth trans would definitely make a better runner....especially with brushless motors.
If you have no connection to this car as it is then, instead of replacing every bit of it, you could sell it and put the money towards a tub car.