I know tech week is over, but this wouldnt have won anyway. I appologise if this has been done before. I bought a bunch of garage sale stuff and was looking through it. In this stuff were a few cheap gauges and a bunch of glass (lenses, stained glass magnafying glasses, loupes and such). Anyway, one of the magnafying lenses fit the lens of a 2" gauge perfectly. If you are an old blind guy, this might help. Either replace the lense completely, or a small dab of adheasive/epoxy the lense over the other. Craft stores sell mag lenses in plastic and glass and you can sand to fit. Plus, instant curved glasses lenses. The pics dont even come close to what you see in person, but the pics do show a major difference. Pic 1: bare gauge Pic 2: with new lense Pic 3: curved glass
What gave me the idea, I was at a different garage sale and the guy was throwing out a stack of plastic lenses. I asked him what they were. He told me they are the lenses for water meters and they are magnified to see the gauges. The light bulb went off and I took his whole stack of lenses.