This is the size after my research. about the upper size, I do it for 16.3cm,
but still little bit small, not actually fit. so if you guys want real fit, I think this size will do.
this is juz the sample if your put the background card into the case something look like it.


Here some of the printing and finished cut look like. the upper pic is original Issue 5 card,
the below is my DIY. Thanks for the "Google" searching high resolution picture.

For the picture you can try imagine yourself for it, can be 3D graphic, illus,
realistic photo, etc... it really interesting after putting in the case.
by the way, is better using the card quality paper for it.

First I must sorry about the photo, cuz my DSLR skill no good at all,
so it juz focus on my tank, background card become blur...
but if it look by own eyes is really look interesting I swear.

the upper is the background I use, the lower is after putting it in.
hope you guys enjoy it, dun shoot me ya... LOL...

here the all my collection again with background.