OK first, what is a GY201?! [sm=confused.gif]

Anyway with the GY401 or GY240 the 3-in-1 merely acts as a main motor speed control if using a seperate controller for the tail. If you check Dume's link Eeeeky said you can in fact use the 3-in-1's tail motor speed control if you take the orange wire from channel 4 hook it into the gyro and hook the gyro to channel 4. Then turn gyro gain all the way down. Keep in mind also that the 401 will require a second channel.

I don't think dialing in the tail prior to an HH gyro install has any real advantage. Chances are it's gonna have to be readjusted anyway. I have an HH gyro on the way too with a seperate speed control. I'm actually going BL, but even if I wasn't I'd go with a seperate controller anyway because I don't really care for the OE 3-in-1. If you turn up the TR trim too much the tail twitches, and you may still not have enough to keep the tail from coming around in a hover. The other thing is the tail will start to wander as the voltage wanes requiring me to readjust the Tx trim during flight.