Here's something I don't actually expect anyone to print. You'd have to have the exact same Mastech meter I have but I figure it's good for idea fodder. The design holds two neodymium magnets (11.76 x 1.6 mm) keeping them .5mm from the surface (may want to thin that just a touch more). The channel in the center is there to allow bending to get the curved posts into their respective cups and the meter hangs on any metal surface.
NOTE: if you DO want to print this for your meter, scale the width down just a touch (about 1.5 mm PLA, ABS will probably shrink more so maybe .5?). I ended up sanding down the nubs slightly to get the flat surface to actually rest flat.
MagneticMeterHolder.stl | 549.5KB |