Use the Hornady kit to check the shoulder....
Or, you can use any cyclinder that touches a point on the shoulder. All you need is consistent measurements, it doesn't neccesarily have to be at the SAAMI specified point.
Still happily answering to the call-sign Peetza.
The problem, as you so eloquently put it, is choice.
He is no fool who gives what he can not keep to gain what he can not lose.
-Jim Eliott, paraphrasing Philip Henry.