I'm assembling my 200-4R and I'd like to replace the stock GN servo with a billet one but the previous builder removed some parts from the servo(spring, cup, etc) and replaced with washers/nut. Check out the pic. The billet servos I'm seeing come with a new piston, cover and some with spring/pin but none with the cup. Can I get a billet servo and use what I have? The clearance with the one in the pic is good. I put the pin, piston, cover(no o'ring) and no spring in the case. Put the snap ring on and checked clearance with a dial indicator. Pushed the cover in until it stopped and had .060. I'd really like to use a billet servo.