545rfe ?s

Not too bad of a price at $799. By the time I added in a PCM, and added in controlling a 545RFE, it was about $1400. I'd have to check Hotwire Auto to see how theirs compares nowadays.
Old thread but this it's the best info I've found so far.
I have an 03 Ram 5.7 545RFE. I want to use the factory TCU with aftermarket ECU.
I understand I need to provide the necessary inputs to the factory TCU - does anyone have info on that, even a wiring diagram would be great.
Thanks for any help!