2000 GMC Sierra C2500 Knapheide Service Body - Only 22K miles on new motor

Ready For Work !!! I purchased this truck over a year ago from a good friend in Alabama. He bought it new in Columbus, GA when he started his A/C business. Well, he made over a million $$$ with this truck and retired when his father passed away to manage all the rental property. Just before he retired he had a new GM crate motor put in it at about 95,000 miles. It sat under a tree in his yard for several years after that and he only used it occasionally. After I bought it, I didn't work out of it for about 2 months because I wanted to make sure it was road ready. I put new magnum shocks all the way around, replaced the "Tarzano" tires with Firestone Transforce A/T commercial tires, new AGM battery, repainted wheels and added trim rings, had a custom metal cover made for the bed... etc, etc. After I started using the truck to work out of the starter went out, then the alternator went out, then the radiator started leaking, then it wouldn't accelerate properly. I was done and parked it for about 6 months. About two months ago I decided this truck wasn't gonna break me!!! After a new radiator, new A/C compressor, tune up parts, mass airflow sensor, throttle position sensor, egr valve.....etc, it still wouldn't accelerate properly. Then I decided it had to be the fuel pump, so I bought a new pump and tank. When I started to remove the fuel tank, I saw the problem, some one had changed the fuel pump before and had kinked the gas line between the tank and frame. I went ahead and installed the new tank and pump, now it runs great. The check engine light comes on at times and has a code for timing and egr from what I can find on youtube the computer has to be reset by someone with a better scanner than I have access to. I'm done, after cussing this vehicle for over a year and putting a couple of thousand dollars in parts in it, I'm ready to pass the baton! What else can go wrong???? lol NEVER BUY A TRUCK FROM A FRIEND!!!!!