I think that you are barking up the wrong tree.

If the issues started when you hit the bump, the problem is probably under your car.

Is your battery in the rear? If so, check it.

I like Klaus' idea, How about running a temporary ground to the tailgate or to the ground terminal strip that is probably under your rear floor. Using a temporary ground is a troubleshooting trick that few people use. You could even add a temporary ground to each load to see if it gets sufficient power to work.

When you have many electrical problems, it is either a ground or you tore a LOT of wires apart!

I would take a good look under the car and inside the car under the rear floor. A small dent on the underside could cause lots of issues if it were in the wrong place.

I had a Chevy Caprice cruiser that had an odd fuel gauge problem appear after I pulled a large boat and trailer out of a river. Turned out that I had a HUGE dent in its plastic gas tank!
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'96 855R,'64 PV544 driver, '67 P1800 basket case, '95 855, '95 854, the first three are mine, heh, heh, 485,000 miles put on 9 bricks