Viperdoc wrote:

All of this is getting to sound expensive as well as being a pain- any
advice or commiseration would be appreciated.

Commiseration only: In the last two years my Bonanza needed a rebuilt
engine, a starter, two new alternators, an overhaul of the STEC HSI gyro, a
new attitude indicator, a repair of the Garmin GNS430 for a failed
glideslope receiver, a repair of the GNS430 for a failed localizer receiver
(both GNS430 repairs happened separately and beyond their six month
warranty period), two batteries, main gear brake lines, and, in what
appears to be a precursor to your problem, an AP that deviates 5 degrees
from either heading or GPS steer course once every six hours or so.

In looking for commiseration among aviation-interested friends locally, I
believe I accidentally scared two of them away for ever owning their own
aircraft.

--
Peter