Okay, when it shuts everything off, what do you need to do before it lights up the dashboard again. That will be the big clue.
If you need to fiddle with battery terminals under the hood, then battery terminals and cables is where you need to look.
If you need to charge the battery, then you need to look for large shorts.
If just waiting a while will work, then it's something on that circuit breaker. The breaker is thermal, so an overload will trip it, but when it cools, it should reset itself. So once reset, pressing with a toothpick won't do anything, because it's already reset. Try testing it right after a start attempt, and see if pressing the breaker turns the dash lights back on.
Try pulling fuses for accessories, particularly the gauge fuse. If you get better results with one fuse pulled, then that's a place to look. (Don't think that this is the issue for what seems more systemic.)
Try pulling the accessory wires that you attached around the water neck. Again, try them one at a time and see if any one in particular helps.
Edit: Ninja'd
Okay, a timing light will check timing and confirm spark.
