Drop in community folder to activate a simple autopilot for the H4 Hercules.  You can control it with control bindings or use the PMS50 GTN750 which has a autopilot control panel in the utilities menu of the paid version.

 The autopilot panel pictured is from the paid version of the PMS50 GTN750 add on. You don't need it, autopilot can be controlled with keyboard commands or control bindings.