I just went and read the other thread (which BTW, should have been posted here from the beginning).

You probably don't want to hear it, but you got the best advise in the other thread, "handheld and custom tune" by a GOOD tuner, but you seem to be averse to doing the one thing that could have fixed your problem years ago. What is the aversion?

Also, I don't know how you have gone so long with the truck in that condition, I wouldn't have made it 100 miles doing that before I was back to the dealer demanding they make it right or put it back stock and refund my money.

To stay on topic;
As far a monitoring; A/Fs, timing, fuel pressure, boost/vacuum are a great place to start.

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