I have the Boost/EGT guage fitted to my truck. I had to wire it up in a hurry as I was leaving cairns for wa the next day. Had some issues I have still not been bothered to investigate let alone fix. They are for the most part a great gauge. The set up is simple. They have a box you put under the dash like was mentioned above. It basically is the junction box that connects all the elements together (Gauge, boost line and thermocouple for EGT). The issues I had was (unless I have wired it incorrectly) it will dim whilst the ingnition is off but not while on. It has boost fully user variable alarm but not EGT( not an issue for me as I know when the temps would be rising and watch out for it). It seems that the diming requires another module to work correctly. If I dim the dash the gauge gets brighter, brighten the dash and the gauge gets duller. Like I say that may be my bad, I mean to call and ask but I have to pull it to put it in my new truck so I will worry then. All seems to operate very well and easily. Seems very accurate and refresh rate looks good too. Has heaps of different colours to choose from and they are aeasy to change if you are driving ant night and wish to choose a dull colour. I rate it about 9/10 (looses a point for no EGT alarm) if i can sort out dim wiring and a 5/10 if I can't. I will get onto them and pull ou the manual again and see if I can get an answer on that for you, I need to know anyway.