This is an old thread, but I just started my own collection of cases and cartridges.
None of your old photos show any longer. Interested in seeing how u attached the brass to the display.

I'm thinking of a few different options, involving a shadow box style frame/case:
1) Glue magnet to bottom of brass case, and make shelves in shadow box with stris of thin steel on top of shelves.
2) Remove primers,and use #4 sheet metal screws, 1/2" long, up through wood shelf, into flash holes.

What worked for you?