Well, I have John Thorn & Graig Kreindler to thank for a link to recently posted images from the Detroit Historical Society. Among the items, proof that Gray Studio was responsible for the images that would ultimately be used by Goodwin for their 1887 Detroit N172s (and subsequent re-issues). Jay Miller and I theorized this to be the case when a Chicago White Stocking proof surfaced of Ned Williamson several years ago (from Gray Studio). The 1887 Chicago and Detroit cards have the same stadium background (believed to be same studio).
Here are some of the long awaited Detroit proofs from Gray Studio:
Can you name these four without cheating?
I find it interesting that some of the cabinets have a faint stamp on the mount as follows:
Copyrighted 1887.
GOODWIN & CO. N.Y.
Copyrights are not known on other 1887 studio proofs, but common on 1888 and 1889 proofs (often scribed into the negative).
I'll share more tomorrow if someone else doesn't beat me to it.