Rough idle, stalls, misfires, & high blood pressure.

First of all, I became a new member of the tundra community today, so, hamburgers and hotdogs at my house tonight.
I'm here to fix my buddy's tundra. (2014 5.7 SR5). It runs great for first 20 minutes, but if that key gets turned off...
Codes tripped:
1. Brake Switch B, input circuit high.
2. Speed sensor A.
3. IAT sensor, high input.
4. Catalyst below threshold.
5. Misfires on any random cylinder,
sometimes multiple cylinders.

It has tripped up to 20 different codes at a time. He first started having trouble about a month ago. He had pulled up under the shade tree and I saw him crawl under the truck to pull the fuel tank for fuel pump replacement..which never got replaced, just cleaned filter on bottom of pump . If you ever get the chance to pull the pump or swap a starter on a 5.7, jump off a cliff. So ..no fix, can't imagine why, so we took a trip to the Amazon and pulled the tank again. Received wrong pump from the Amazonians, so old pump in again. (Daily driver for work). I'm sure OEM parts are the way to go but he isn't ready to take out a loan for parts. They're expensive. Really expensive. He tried new plugs and coil packs, cleaned MAF, and IAT sensor. There was a loose wire in MAF/IAT harness, fixed it. Pack rats are thick around here but have found 0 evidence of wire gnawing. Fuses and relays are up to par. Fried the starter in the process.(bad battery connections), reman installed, fried it, fix connections, new starter installed.
Sometimes the truck has a great day, and sometimes we get to test his tow strap. Just looking for someone with better ideas than ours. Any help is appreciated.
THANKS!
Lord Ringworm

Also wanted to mention that it takes fuel from gas station extremely slowly.