Okay, appreciate the feedback guys. Since last update I've ....
1) Hit panic button and horns blast okay.
2) Remembered truck was in for airbag recall check at dealer.
3) It's possible I have not tested the horn since airbag recall. Clockspring not hooked up after recall?
4) Only thing not working is horn from steering wheel. Cruise/lights and everything else okay.
5) Will give the hard reset a try as suggested by Seafish
Might be a few days to a week before I can post an update, but any new feedback is welcome!