The build continues. I temporarily wired up the controller, receiver, speed controls, GPS and connected to Mission Planner using my desktop PC. It is not easy to figure out exactly how to wire it as the new controller had no documentation! I found some useful information on the Ardupilot Wiki and found a basic pinout here. Hooked it up by USB and it seemed to work, but...I had the controls all wrong. After playing around with the radio calibration screens, I got the rudder, throttle, ailerons, elevator mapped correctly to the controller. I could then calibrate the compass, accelerometers, radio, etc.
The I had a brilliant idea (uh-oh). Since I would be programming things in the field, I should use my laptop with Mission Planner to set up the drone. Well, for some reason the laptop did not like to calibrate the compasses so after a few hours of frustration, it was back to the desktop where everything worked. There was also the issue of the compass being off by 90 degrees due to no markings on how to mount it, but this was easily fixed. The compass is mounted with the GPS on the wooden tower in the photos above.
Next steps are to tidy up the wiring and mounting, calibrate speed controls, attach props, and do some testing with the unit tethered to make sure it is set up properly. Stay tuned.