I'm doing a bit of research (and yes, im quite famililar with the search button), about installing a Ramjet502/572 into a 2004 Avalanche 2500. Rather than using a built 4l80 with manual shifts(no need for computers), I'm preferring to go with a 4l80E built to the task. Anyone have any opinions on stand alones that you used, or in an GMT800 truck and retained any stock functionality? Just trying to weigh how difficult this swap will be on a computer basis.