Ok, did a search, found a lot of info but not the exact answer to my question. Ok, so I'm looking at getting some gauges: Now I want the defi's for sure but I'm unsure of a few things. I want the 52 mm size gauges but I can't find a defi a pillar mount (already have gauges in pod) will they fit in any 52 mm a pillar such as an 3 gauge autometer? secondly defi's simply put are expensive: I want to get the the "link" series EGT and possibly boost cuz of the peak and warning functions, but I don't want to spend that much money on the other gauges. Therefore, I want the cheaper "D" series for the less important ones. So I guess my question is, can i use the different guauges together incorporated into the necessary Defi-Link Control Unit II? Can the "D" series link up to the Control unit? Sorry for the long complicated questions - please help!!!