Yes, the springs were more-or-less custom made. They knew the dimensions of the springs, I just told them the weight of my truck, and the desired lift amount. There are 12 leaves in each spring pack! Heavy, but the ride is very smooth, and they flex great. (You would lose an inch of ground clearance under your springs if you did this on a spring-under.)
To get back on topic, the tranny temp gauge in this truck is the same setup I am going to install on my other truck.
On a hot day, I might see temps of 180, up to 190 under load. If I'm climbing hills (mountain roads), and hard on the throttle, it will hit 200. I back down the throttle before I hit 190. If I do get that hot, I pull over and let things cool off for a few minutes - to be safe.