Thanks for your great post.
Im going to be pulling the dist to perform the things you recommend. Seal the hall switch plug against moisture, ditto the ignition wires.
Also will go over the other things you recommend.

In addition I recognize the hood seal is not performing its job. The long rubber piece held against the fire wall with little plastic retainers. It forms a seal with the hood when the hood is closed. Some of the retainers are broken and no longer holding the seal in place. Im thinking this is big part of the problem.

The seal also forms a drainage channel between itself and the firewall. I think the idea is to stop the water before it gets into the engine compartment and allow it to drain off to the extreme sides of the engine compartment. Im wondering if I should apply a sealent between the seal and the firewall.

Thanks

Larue