2002 f350 7.3 Oil leaks, shuttering, loss of power, black smoke

Hey I’m looking for some advice on my truck. I’m a contractor and have some mechanical abilities but my knowledge is just what I’ve learned over the years and what I’ve read about so please give any advice or suggestions in layman’s terms please. I had a bullydog tuner put in my truck about 5 or 6 years ago and was so excited because it ran beautifully. About a year ago I was experiencing some oil leaks and my “buddy” said I needed to do the head gaskets so I had him do it. Then I had a lot of oil in the valley of the motor again so he told me it had to be the turbo pedestal o rings. I bought the new o rings and we took it all apart (this time I wanted to help so I could see for myself what was going on) and when we took the turbo off the waste gate plunger (I believe it’s called) was very loose and had oil coming out of it. He told me that it was unnecessary to have and with some backyard mechanic techniques it was removed and sealed and the new pedestal o rings were replaced and everything put back together and it seemed to run ok. Then a few weeks later on Halloween last year there was oil in the valley again and I took rags and soaked it up and he said we needed to wash it off so we went and degreased it and washed it which resulted in my truck not starting and having to be towed back to my house where he proceeded to mess with a bunch of wiring and cut my brown wire with white tracer on the engine side of the main wiring harness (ecm or pcm?) and put small cuts in the same wire in a few spots across the engine bay for his multimeter trying to trace the issue. After exhausting all his thoughts on what it could be I decided to try the truck again and it fired up with no explanation on what made it work again (mind you this was over a 2-3 day period) in the meantime he said he “updated” my tuner (which he doesn’t have the software or programs for) and disconnected my ebp sensor saying it would make it run better and I’m honestly not sure what else because he’s ghosted me for the last month and a half. Whatever he did I’ve had my check engine light on since and my trucks coming up for inspection. Before he disappeared I took him for a ride to listen to what I explained as a ticking noise as I accelerate and he said maybe an exhaust leak but didn’t check anything out and it’s only gotten louder since. So to this point the last few weeks through research and forums I have reconnected the wires properly (he just had a red jump wire finger twisted on my brown/white tracer wire which was making my truck cut out while I was driving) taped all the other knicks in the wires, checked the icp sensor for oil ((it’s dry and only a couple years old) replaced the king nut on the oil pan and new dipstick holder because that was leaking, degreased the underside of the motor properly so I can trace the leaks and installed a new piece of tubing on the backside of the fuel filter housing that wasn’t hooked up to the aluminum/steel tube to take the waste out to the front of the motor like it’s supposed to and not dump it in the valley. I still have a decent oil leak happening and while it was clean and I was underneath I noticed the bottom of my up pipe is corroded and the bolts holding it together are the size of toothpicks and unrecognizable as bolts. I believe that’s why I’m getting the ticking noise and loss of power and black smoke (correct me if I’m wrong) I also on average get 4-6 pounds of boost if I’m lucky it will jump to 10 for a split second but also reads 0 more often than that. All that being said I just ordered new up pipes the pedestal delete kit and the pigtail for the code to go away and a fooler? So when that comes I’m going to put it on and check around the backside of the motor for any other issues that I can’t see with everything in the way. I have 4 codes and the one goes away but the other 3 are always there they are p1280 p0475 p1211 and the one that went away was p0460. Do I need my ebp plugged back in for my tuner to work properly? I read that in a comment somewhere and also is there anything else I need to do while I’m replacing the up pipes? I need these codes and my check engine light to go away for inspection in august and I can’t afford to be without my truck for days so any insight or advice would be greatly appreciated! Thanks