I am going through my new 62 and have read about installing the external transmission cooler as well as a external gauge. I have decided to go with the ISSPRO ev2 series gauge. It is the 2 1/16" gauge so it will fit in the space below the A/C control. My question is they offer one that is 140-320 degrees and another that is 100-280 degrees. I was going to purchase the one that is 140-320 but I wanted to get some opinions on this, I don't want to purchase a gauge that isnt going to register until I am towing something. Any advice is appreciated. Thanks