Findings thus far. This is info collected from the interwebz so I can't validate the accuracy of the sources:
For a totally OEM conversion, in addition to acquiring the wiring harness, there is a module (virtual?) to be programmed in the BCM for this. The problem is that turning this function on affects the turn signals and they won't operate properly or not at all. I guess vehicles that came stock with these things had a different turn signal system. AMP Research sells replacement parts and their controller module is $92. I'm sure the part of their wiring harness that plugs into this controller would be needed as well. But, I don't know if the AMP motor assembly has anything special built into it for the controller to know when the step is fully extended or retracted or jammed anywhere in-between and if it works by some sort of trigger or current draw or both. If the controller is fully self-contained and just has two wires to operate the motor, theoretically, I could simply follow their instructions on hooking up the AMP controller to the Tahoe, then connect the motor power wires from the controller to the OEM step motor. But, if the controller operates and senses the step's movement based on amperage, there's no guarantee that the OEM motor draws similar amps when operating as the AMP motor does.
Call me lazy and poor, but there's too many uncertainties for me to begin investing the time and money into something I was entertaining only because of the cheap initial cost. It's looking like a project that will snowball well beyond the point of being worth it. Even then, it's something just for a small "cool factor". I'd rather just spend one dollar amount for what I consider a better cool factor: The $150 for the coil relocators I need as the final component to my drop.
In all of my digging, I ran across something that I think I'll be satisfied with: Adding a 3/4"-1" wide strip of chrome trim to my running boards and along the back bumper to mimic the Denali and Escalade trims. I'm not big into bling, but I still wanna add some classiness to what I believe is concurrent to the LTZ trim level. The simple chrome strip down low will tie the black plastic of the steps in with the wheels and door handles. If I decide that it's too much, it'll come right off.