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Hello, thanks for the detailed background.
So far it sounds like electrical spikes from the power failure have damaged the electronics in the blower controls including one of the printed circuit cards.
Tell me a lot about your technical skill sets, and if you have a multi meter or not... that will allow me to coach you most effectively.... if have some of those skills and a few hours to spend trouble shooting use the paper clip icon at the top right to send a very well focused, well lit, close up photo of the wiring diagram glued inside the blower compartment... take it from straight on, not at an angle.
I will mark it up with trouble shooting instructions, we can go from there.