If you just get an escalade cluster it has a tranny temp gauge and it's plug and play. It's already in the harness for it. Stock thermo will be fine. Install should be easy since the kit comes with EVERYTHING. Definitely get it tuned afterwards because the stock radix tune leaves A LOT on the table. Any tranny cooler w/a GVW of 25K should be fine. 2600 stall is going to be perfectly matched to the charger. If the price is different between that tranny the the FLT level 5 65e I would just go for the cheaper one. I havent heard of anyone busting one yet and plenty of people are pushing 500+ hp through them. Sounds like you made a great purchase :head: