Has anybody ever attempted this? or have any ideas on how to? Any help would be appreciated

I've not used shot glasses but did use stemmed wine glasses. Just be sure to put a dowel in to support the glass.

Hi! Are you talking about separating your cakes like this?

http://cakecentral.com/gallery/1350608/yajairas-love

I've only separated cakes with champagne glasses. I guess the process would be the same depending how you would want them placed between two cake tier plates. HTH