Tailstock alignment.

[petertha]

Tony has a very rigid & compact assembly to hold the indicator. But just a word of caution if you were thinking to replicate the rotating indicator action with a typical mag stand. All bets are off as gravity can act on the extended arms & joints. The dial will read differently upright than inverted & depending on the extended arm, even laterally side to side. I've attached a RK video link below.

I crudely mimicked this with my equipment & got the following on a mini mag holder vs typical mag holder. Your mileage may vary.
Noga 6"? Mini + Mitutoyo 0.0001" DTI: Level reference = 0.0000", 90-deg = 0.0005 - 0.0008", 180-deg (inverted) = .0011
Noga 12"? + Mitutoyo 0.001" DTI: Level reference= 0.000", 90-deg = .0042", 180-deg = .0055" (suspect a smidge more because it didn't return to zero & there might be some flex in my bar).