So the fuel pump started priming all the time, not just for a few seconds while key is on and kill switch is flipped to run. And shortly after this started the full throttle issue started?
If I have it right it sounds like you need to pull the fuel pump, replace the screen, filter and repair any chaffed wires.
That's where I'd start since is sounds like the constant running pump is grounding out due to chaffed wiring.
Check out the fuel pump rebuild thread for a bit more guidance.
Good luck