Dan - Great job on an upgrade! I didn't want to post on the thread without verifying...... The old system trigger closed a ground. I noticed yours puts power to the trigger.
I remember recyling my old clock power wire to put a momentary switch on my overhead console. Since it was an unconnected ground, I was happy with it. Will your trigger wire be powered all the time? I would have concerns running a power wire all the way through the aircraft that isn't controlled at the master.
Am I thinking correct?k