I have a 1998 gmc 2500 classic sierra with 5.7 and 4l80e and I'm removing the 5.7 and putting in a cummins diesel. I have almost everything lined up besides how to control the 4l80e. I found a few costly stand alone units, but someone recommended finding a "16196390" ecu and reprogramming it to just run the transmission using a few sensors (tps,tach, ect).

After much googling I landed here. I installed both cats & tuner pro, but I dont see the bin file for 16196390 .

Question 1:
Is 16196390 the only computer I can use? could I get a different computer (1227747) and reprogram it as a transmission only controller?

Question 2:
If I can reprogram one of these controller to just run the transmission, could I test it in my truck by using an secondary transmission harness to wire it directly to 4l80e? So it would use the engine management from the original controller and use the transmission controller from the 'new' reprogrammed controller? It sounds silly, but i could easily debug issues while I have a working truck before I do the diesel swap.

Question 3:
Is there any option to just remove the engine management from my stock ecu and just use it a transmission controller?