Fitzgerald's Baseball Cards Mystery?

Hello folks! I'm a new member here and plan to use the Forums for my interest in Great Literature.
It's actually a sidebar type literary search which pointed me here and I'm hoping some of the knowledgeable scholars on Fitzgerald may be able to solve a mystery for me with some substantive, verifiable information.

Here's my question.
There have been some largely unverifiable indications that Fitzgerald may have had a collection of tobacco style baseball cards as a youth and young adult which supposedly were still in his posession until his death.

With Fitzgerald's evident disdain for the social stratum that the game of baseball attracted in the early 20th century (he would often chastise his friend Ring Lardner for wasting his literary talents on baseball related fiction) I wonder greatly about such claims.

There are cards in collectible circulation which have been attributed to having belonged to Fitzgerald because they have been stamped on the back with a Victorian Style letter "F".

1) Does anyone in this community of Fitzgerald fans know of any such marking habit used by Fitzgerald; either on baseball cards or any other property? Does that stamped letter appear anywhere to your knowledge?
Is what you know or understand about it, verifiable? Photo, Scan, web link?

2) Can anyone substantiate or reasonably debunk such a theory?

Comments would all be appreciated.
RayB