Matt I have one of DArcy's boxes in my 7mm Mashburn Super,and follower as well. Function is flawless.
I like the photos. That Echols stock with the bare bones no paint finish grows on me by the second. I like it a lot and if my stock looks as good as that, it ain't getting painted.
So are you going to use the box in a pre 64 or are you going to seek a short M70 Classic for the project?
Decisions...decisions..