97 K1500 electrical problems

I have a 97 K1500 Silverado. It started going dead for no reason about a year ago, this only happens sometimes. Often it will be fine for months then it starts again, its ruined the battery so now it has a new one, same problem. I changed the alternator 2 times( That keeps going bad also). After it started going dead the alarm would go off for no reason, after about 2 weeks of that the interior lights started coming on by themselves then wouldn't go out, I removed the fuses and the switches, lights stayed on so I removed the bulbs. Then a few months later the doors started unlocking themselves, then locking themselves both while parked and while driving, now the door locks dont work at all, except they still unlock themselves sometimes. Then the power mirrors stopped working, first the left, then the right. I cant find any loose grounds. Is there some kind of a module somewhere that runs this stuff? Any suggestions? By the way, there are no codes for anything and a computer scan shows everything is fine.:runaround::runaround::runaround::runaround:: runaround::runaround::runaround::runaround::runaro und: It's making me crazy!!!