well if you want a purely rocket powered R/C you should remove several components. First off take off the entire tranny and motor. Then take off the battery and any battery mounting parts. Also remove the ESC and mounting parts. You should power the RX from a rechargeable 5 cell pack. Also remove the differentials and driveshafts of the car. You will need to keep the axles in so that the wheels will stay put, but upgrading to bearings at the axles would be a good idea. You will be able to use a 2ch radio for this R/C since only one channel will be needed for steering and the other channel can be used for igniting the rockets. You should look into the pico switch for igniting the rockets. It will weigh less than adding a servo to manually ignite the rockets.