I think it's nothing more than repinning the transmission section of the harness. If you know a transmission man, borrow his ATSG service manuals and make copies of the pin outs of the 4L60e and the 4L80e and change whatever is different. You and Red should be able to figure it out without any issues. I'm thinking they both have the same connector, the pins are just in different holes. If you can't do it, take the harness off and send it to John and maybe he can repin it for you for a nominal fee.