Battery draining overnight

So here is what I have done. I called Powermaster and talked to their tech guy Chris. He said to just run an 8 gauge wire directly from the alternator to the battery and not worry about the wire that I had going from the alt to the ammeter. I installed the 8 gauge wire, but instead of just capping off the ammeter wire, I connected both ends in the engine bay to the big post on the starter relay, and then connected both ends of the interior side to a single post on the ammeter. I hooked the battery up and everything seemed to work fine but I could see the battery was still draining with my multimeter. I disconnected the alternator and the battery stopped draining. I guess I’ll be sending it off for repairs now.
Sorry you had to discover that the hard way.
The ammeter was your friend here.
If you hadn't checked for a drain after making those mods, a lot worse damage could have occurred.
Its good you used your head. :)