I recently added some wonderful OEM gauges to the dash of my "85 240 thanks to a brickboard member in CA. Had recent thoughts of some add'l mods in the form of an altimeter. Most of the one's I see online are for RVs and mount on the dash or on the windshield via suction cups. Is anyone aware of an automotive-use altimeter that is small enough to fit in-dash like in a Volvo's 2-1/8" dash pod opening? That would be the crowning-jewel of a dash gauge for me! Same size as the VDOs but giving altitude, and of course, adjustable for barometric pressure changes, like the RV types. No, I don't need an "airspeed indicator", too! Most of the sources for aircraft types, show altimeters that are too big, too deep, for auto use. Also TOO expensive.