Hi Ted,
Powell is on a different plate scratch sheet
this one...
https://photos.imageevent.com/patric...et%201A-1B.jpg
this is the other plate scratch sheet that the back was used on two sets of fronts. One sheet is all SC649 subjects and the other is all 649 no prints.
Shaw is the matching scratch to Powers
Powers-Shaw 1.jpg
actually two of the Plank Piedmonts have the same scratch but I
haven't found any scratches that they match up with.
Plank A.jpg
Plank B.jpg
Luke just did a four part article on his site that covers this and he does
a much better job of explaining it than I do.
http://www.thatt206life.com/