[John S Peterson]

I think you have more than one problem. I think you have a voltage drop at that battery cut off switch (never turn that off before engine is off) and also a bad battery. I have nothing against Optima's, but if you can take that one out and have it tested or replace it with a known good battery. A bad or weak cell will fool the alternator into charging when it shouldn't. It can't be your ign sw because you say everything goes out. If you know how to do voltage drops, just do one circuit at a time, you'll do fine (new kill sw)