I plan to install Trojan T-125s in a 36CKTS I am ordering soon, but would prefer T-145s for the extra capacity.
Have you considered if there is enough room in the battery compartment opening to get the taller T-145 batteries through, including room room for a battery carry strap and your hands? The T-145 is .83" taller than a T-125 or T-105.
.83" doesn't sound like much taller, but I have wonder how tight it is there since I don't have the FW yet and need to buy the Trojans before traveling to the dealer for delivery.
Chris and Pat
2016 Ram 3500 Cummins Aisin Dually
2017 Cedar Creek 36CKTS