I was thinking of basing it on a MiniMac system - cheap
& cheerful and it could be remotely placed to protect it from the elements. There are a lot of automobile systems that use a DC-DC converter to power the Mini and you can also get automobile 12V screens for your display (though you'd have to be canny about the waterproofing).
Anyway, I've just today received my BU-353 UPS GPS
, tried it with GPSnavX and can confirm that my desk is not moving and that it is located in Hong Kong
. I'd have to wait till daylight and climb a mountain to do that with my sextant!
It really is beautiful software and I think I'll just go ahead and purchase
a copy of MacENC.