2016 L83 8L90 Standalone WOT Stumble

I have a junkyard 2016 L83 8L90 from a Tahoe in a 56 chevy truck. I've done all the harness and ECM programming myself. The internals are all stock. I have a custom cold air intake (same diameter as stock). Stock manifolds, 2.5" exhaust, no cats and borla mufflers. I am no expert, this is my first go at standalone. I am experiencing a stumble/rev limiter (backfire) at about 4800 rpm. On the data log I can see the high pressure fuel drops dramatically when it stumbles. I have disabled the DOD. Not sure I have disabled everything I need to.

I am also getting a lean code