65 Valiant now gauges go full when ignition key turned or running

I really just don't know what else to tell you. If a solid state regulator sends about 5 volts through a gauge and out to a sender, the bulb in a 12 volt test probe isn't going to verify voltage unless you're in a deep dark hole.
I'll back away gracefully. Other members who own 65 model and/or RTE regulator may not need pics, etc... can help you. Good luck with it.