Hiatachi mini-starter/Electrical bug

[OleSenna]

I had a mysterious electrical issue with ignition coils going out on my '72 Blazer when they got hot. Battery is fine, but truck is currently (no pun intended) not getting power anywhere.

It has a Painless wiring harness installed by an expert audio-turned-fabricator guy 5 yrs ago, and a crate smallblock with a MSD street billet distributor (no CD box). We replaced the second MSD Blaster 3 coil a week ago with a lower voltage energy coil, and it seemed to respond well.

Then we did some mechanical fuel pump plumbing work. When we went to fire it up, the coil wire came out of the coil tower and arced across the coil primary wires and tower. By the time we stopped trying to start it, we had lost all power to the switch and to the coil. Thought we'd burnt a starter solenoid, so we replaced it. Thought we'd burnt an ignition switch, so replaced it, too. We now have 2.3V at the alternator, and still no power anywhere.

The (+) battery cable is connected to the upper stud of the PSL100 Hiatachi starter's solenoid. The starter motor lead is connected to the lower stud. and the purple starting wire from the switch is connected to the small side-lead.

We are not 100% sure where the red and light-green/light-blue primary wires, which were connected to the solenoid, go.

We had them connected on the same stud with the (+) cable, but, after questioning that setup, we checked the eyelet impressions left from previous arrangement. Sure enough, the red wire's smaller eyelet left an exact impression on the heavy U-terminal on the lead going from the bottom stud to the starter motor. We were afraid to connect it there since it didn't make sense to connect the red alternator wire to an intermittently energized starter motor lead. Maybe we are missing some piece of the puzzle.

The questions are:

1. Does anyone know where the red and green/blue (teal color?) wires go (coming from the painless harness to the Hitachi solenoid?

2. Could blown alternator diodes or the internal V. regulator, which is giving 2.3V, prevent the switch from getting power?

[OleSenna]

A bit more info on the situation, which might help with the diagnosis: The inside of the distributor cap and top of the rotor were coated with ionization (rust-dust), which we cleaned before installing the new 3rd coil.

The double-platinum plug gaps have reached .050. We figured with the old-school carbon-core, albeit 8mm, plug wires the coils had reached the point of over-load.

The second coil gave up not long after the first. Once they'd cooled off, the engine would crank and go a short distance before shutting back off. We have a set of low-resistance spiral-core wires to put on, but lost power from the starter on, so we've been chasing that problem first.

The truck ran well on the way home with the new coil, especially when you consider that, the next day, we discovered the Edelbrock AFB carb floats were way high, which together with the ignition overload were causing the exhaust to be totally rich.

Thanks in advance for any assistance!