I'm picking up my new travel trailer today (Apex 235bhs - 4277lbs dry) and have everything ready to go including a brake controller and distribution hitch. My truck is a 2011 TRD sport with the towing package. All I'm missing is a gauge to monitor the transmission temperature. I already have an ultra gauge, so I don't want to buy a scan gauge. What are my options for a stand alone transmission temperature gauge?