I have just installed the 3e in my Carf Corsair. The Corsair uses the older Royal RRS. When installing the 3e gyro it is important to note that the gyro patch lead that runs from the 3e to the receiver must be modified to work properly.
Here you see that I have the gain plug in my finger tips and will remove the red pin prior to installing it in the gyro.
This is what the screen will look like if you do not do this.
This is what the screen should look like.
Here you see the pin has been carefully removed from the plug. Just lift the tab with an exacto blade and pull out the red wire. It can be taped back on the wire if you like to keep it safe and neat.
Here is the plug after being modified. Now just push it into place on the 3e gyro and you are done.
Enjoy this little marvel !!