The part after "My plan...." makes the most sense to me considering the pitfalls already discussed.
Sounds like there needs to be a harness made. Something a little less than a mess I mentioned earlier but with enough pinouts, it can't be that hard.....just time consuming. You need to design a harness that adapts the external TCM originally from a 4L60/65/70E from a GMT900 to a 6L80/90E style hook up to the same platform truck.
I guess?
