Probable fix found
So, I got the LIM installed and let her sit overnight. I fill her fluids up, got the fuel pressure up, then fired her up. Same damn thing. Running like crap.
I go under the hood and hear a absolutely terrible vacuum leak, now. It is driver side, lower than the upper plenum. I grab some old garden hose, cut a length off and use it to spy around listening for the leak. Can't pin point it. I spray around listening for an idle change. None.
Then, I just happen to move the insulation for the egr up-tube to the plenum and the pitch changed.
I slide the insulation all the way up and she runs worse with the vacuum leak noise being enormous.
She has a rust hole in the up-tube. Apparently, when the insulation is slid down, it hides the leak, for the most part, and didn't allow the spray to get there to locate either. Most probably, when the egr opens up or closes, the leak changes enough to cause surging?
I know now where my next step is. Finally.
At least the LIM is new, fuel injectors cleaned, and everything above is like new.