Seeking AP Control Head Suggestions

[hpeer]

I am looking for a Auto Pilot control head that will provide a 12VDC output to my steering motor.

The steering motor is the drive part of a CPT auto pilot and it is perfectly strong enough to steer the boat. But I have a variety of problems with the CPT control head.
Magnetic deviation in a steel boat
Control head placement
Propwalk under power

I thought I had a solution in the PyPilot gizmo. But that had a few issues I could not over come. Not the least f which is it is incapable of driving the boat with prop walk. The Developers design criteria is the boat needs to be perfectly balanced, and since it is a sailboat you should always sail. There are additional issues.

Being a steel boat I need something that will take a GPS heading. It needs to be able to compensate for prop walk. And the output should be at least 2 amps drive current. It should be a stand alone unit, not tied to a Chart Potter. It needs NO course following, just point and go, I will make course corrections.

And of course I beed to be able to mountbit so I can use it without leaving the cockpit.

I know there are a number of folks developing audrino AP’s and the like but have no good knowledge of them being used. Any options come to mind?