Oo. My wife is a bit of a gear head when it comes to our CTD. She took it last week to get a new pacbrake installed. Then she compared the weight of our new trailer vs. the old and decided I needed an Edge EZ chip. Yes, she even paid for it! Installed it this afternoon. Now, I've got a couple of questions... Going towing next week west over I-70 including Eisenhower Tunnel and Vail Pass. I don't have an EGT gauge YET! First, is level 4 , edge default, safe without gauges? Second, is it safe to install the elbow without gauges? Don't flame me! I promise to get an EGT gauge before I go towing next. Thanks!