I got the wiring diagram from the guys at HEAT. (trouble linking to their website so see the attachment. No rewiring required, just the use of a 'Y' connector. This allows the Rx to control the servo AND still send a signal to the MFU to generate the turret motor sound.
Instead of the servo rate reducer they recommend, I got the Camera Position Controller because I use the stock Tamiya Tx stick arrangement.
Ratcheted stick - Servo Rate Reducer
Self Centering Stick - Camera Position Controller
http://dionysusdesign.com/product_in...roducts_id/190