Paul Griggs wrote a comprehensive article in Issue #18 of
Old Cardbaord magazine, including a full set gallery, display of three different back variations and examples of other sets that use the W554 images. You can see an abstract of Paul's article at
www.oldcardboard.com/misc/issue18/issue18.asp.
The W554 Gehrig pose is also found in the 1933 Goudey set. Unless I am mistaken, 13 of the 18 W554 players are now in the HOF.
Lyman