Thank you to those who provided details (many prior to my post some as a result of this post). I have the details I'm after from Jay M., Jon C., Kevin C., Joe L., Henry M., Peter F., and of course my packs.
There remain a couple periods of time for which I'd like to study the pack details a bit closer including the following:
Any 20 count packs post 1887 (may not exist)
Any pack dating between Nov. 1887 and May 1888
Any pack dating between Nov. 1888 and July 1889
The last two help identify transitions from one style slide to another.
Every thread deserves a picture. Here are the earliest 20 & 10 count packs I'm aware of, Feb. 1887 (20ct) and June 1887 (10ct). A second copy of both packs with same cancel dates are known.
