Ardupilot Rover 4 Wheel Steering

Setting up 4 Wheel Steering for Ardupilot Rover on my Rock Crawler.

Need to connect the second steering servo to Channel 5.
So now there is one servo on Channel 1 and one on Channel 5.

Set the Channel 5 Parameters to match Channel 1.
RC5_TRIM = RC1_TRIM  (For me it was 1078, this may vary by servo.  This will set the center of the servo.)
RC5_FUNC = 26 (GroundSteering)
RC5_REV = -1  (This will reverse RC1 value)

You can find the definitions of all these values here:
http://ardupilot.org/rover/docs/parameters.html

I still need to get the throttle correct.  Mission planner shows the throttle at 100% even though its at its lowest point.