RE: instructions for changing the motor in my RC18T ?
look at the motor mount there should be 1 screw on top of the mount and 2 screws on the bottom of the chassis holding it in place remove all 3 screws from the motor mount and it should move around (the motor will still be attached to the mount) then you will see 2 screws holding the motor to the motor mount remove these screws as well (this is where you adjust your gear mesh)
and with a little moving around the motor should come out it is a bit tricky compared to a 1/10 but very doable you do not need to tear the whole rear end apart 1/18s are a bit tight but once you fool with it you will get it sorry but thats all i have for instructions