Bartamos, I was also thinking about the ground subject. When I was trying to confirm that horn #1 was causing the battery drain, and with the battery and horn relay still both fully hooked up, I removed the mounting nut from horn #1 (the mounting studs for the horn are integral to the horn housing and mount through L shaped mounting brackets bolted to the firewall.) I then started to lift the horn out of the mounting bracket (which was still mounted firmly to the firewall), and as I pulled the horn mounting studs out of the mounting bracket, it was sparking all the way. I presumed, maybe incorrectly, that such was an indication that it was finding a good ground and that something inside horn #1 was an issue? Not true?
Carl - thx for clarifying that such is normal! As I want them to be on also when I pull the headlight switch all the way out (with the headlights), I’m going to run a jumper from the Park to the Tail connections on the headlight switch!