TW 10.5 arm overhang set up?

Doug,
You clarified that better than I ever could have.
The mirror is so important for those micro alignment adjustments. It's just not possible without it. Once you have a Mint or Wally (and use it to its fullest advantage) you will see (and hear) this for yourself.

I agree but there is a line on the protractor that needs to align with the stylus. It isn't as good but it s very close.

O will admit I am a VTA/VTF believer over HTA. I hear it much more and measurements seem to agree with me.

...I am a VTA/VTF believer over HTA. I hear it much more...

Fair enough, so do I in some cases. Of course this is cartridge-, system- and listener-dependent.

Another use for a Mint or Wally is setting initial azimuth. That squared-up view of the grid, cantilever and their reflections makes it easy to verify that the stylus is oriented precisely to the vertical. When the stylus and its reflection form a perfect "X", azimuth is very close. Fine tuning from there while listening is easier, faster and more enjoyable than fussing with a Fozgometer, Wally Analog Shop, ocilloscope or voltage meter (unless you prefer fiddling to music, lol).

I get a lot of mileage out of this $100 tool. The Mint and a VTF scale are the only measuring devices I use when setting up a cartridge, typically in 30 minutes or so. I can't do it so confidently with any of the lesser protractors. Of course YMMV!