94 Chevy Automatic transmission

I have a 94 k1500 chevy with a 350 and a 4l60E transmission and I am wondering where a transmission temperature gauge should be hooked up? Currently I have the sending unit between the radiator cooler and the aftermarket cooler I installed on the front of the condenser. Also curious what temperatures most other people run at going hwy speed in overdrive. I am running about 210 degrees going 70mph down the interstate in overdrive. I average about 185 degrees in 3rd gear when pulling a 4 place snowmobile trailer at about 65 mph. Thanks for any help.

mines a little cooler than that.

My temp gauge inside cab reads approx 195-205, not sure if your asking about engine temp or tranny temp 'cause don't transmissions run alot warmer than the engine? I know thats why trans fluid has the properties (viscosity resistance) it does vs. req motor oil