Fuel pump running with engine off

Well, I let the engine idle and ran the heater and defrost for about 15-20 minutes and the problem behavior has stopped. I would venture a guess that the large cab leaks I have played a role in this fun. Going to leave the battery disconnected overnight just to be safe since I don't want to burn out my fuel pump or create some other problem. Maybe I should just pack the dash with packets of dessicant? I should have time tomorrow to pull the ECU and inspect it. Fingers crossed this was just enough moisture to cause a problem but not enough to ruin anything, or else it's gonna' be
Although I only purchased this truck to have as a RELIABLE and EASY backup/day-off truck I am kind of enjoying getting to know some of the internals here. The only tragedy in this is that I may fix all this and learn a lot, but the leg room will still be worse than my old 1985 Toyota Reg cab 5spd.