Well after all my drama of getting the thermostat out initially. I did end up getting caulks piece installed.
I didn't feel comfortable with the amount of fluid I lost, so I grabbed a quart from the dealer to top off.
Following the fill procedure provided by
@Wild one , I was surprised how high I had to jack the rear end to get the pan level.
Edit: I'm really surprised, researching all the 8speed fill procedures I see on YouTube primarily, no one mentions or does adjust the truck to get the pan level.
The fill plug location is a PITA. I also had a bonehead moment, when I went to crack and back off the fill plug prior to going through the procedure and accidentally backed it off too far and took another slight bath in trans fluid and soaked my freshly wrapped crossover pipe. D'oh!
Ambient temperature was right around 84* so used a fan to help cool down the trans prior, but I assume I went over the 86* temp threshold.
Ran through the procedure and topped off the trans fluid.
2019 Ram 1500 Classic, 5.7l, 8speed, 4x4, crew cab stock truck temps during mostly flat highway drive across Texas at ~85mph w/ 79*F ambient temp. Redline 5w-30 oil w/ 65XXmi and Royal Purple 10-48 filter.
Mods: 180* coolant thermostat, caulk trans thermostat bypass, AGS deleted, stock v8 fans deleted, v6 fan installed, a/c on.
Highest temps (+/- a couple deg) I observed driving through some hillier parts of Texas, cruise at 85mph, 99*F ambient temperature according to truck.
redline 5w-30 oil w/ ~3k miles, Royal purple 20-820 filter.
While driving mostly flat highway across Texas, ambient temp f/ 85-100*F, at 75-85mph these were generally the average temps I observed.