To connect the gimbal, needs three female-female wires.
Tilt: Connect one of your wire in T pin. Connect tilt to Erle-Brain channel 5.
Roll: Connect other wire in R pin. Connect tilt to Erle-Brain channel 6.
Ground: Connect one of the wire at ground "-", only one ground is needed.
Note: If you are using a Erle-HexaCopter you have to use the #7 and #8 pins in Erle-Brain 2