I'm considering adding an EGT to my 2002 GMC 2500HD, but I don't see a need for boost or any other instrument. I already have tranny temp on the dashboard. So am I being penny wise and pound foolish to install just the one instrument in a single-instrument pod? Or would I be smarter to install a dual-instrument pod and leave one position unused? I don't want to diminish resale value by making it impossible for the next owner to add a second instrument, if that's what's most often done (I'm new to trucks in general, so how would I know!), but I don't want to spend more than I have to, either.