Clamshell Size Question?

[TrekStar]

I have a couple of custom figures with custom art card backs, unfortunately the card backs
that I have do not fit proper in the EMCE removable clamshell cards.

I could trim cut the tops or bottoms of the cards, but that would cut off the lettering print
but the width of the card doesn't fill up the space.

The custom card back length size is just under 10 inches by a smidgen and the width size
is 7 inches, the EMCE removable clamshells are 9-1/2 length size and 9 inches in width.

I'm assuming the FTC clamshells would be to small especially the length.

You can't cut or trim the clamshell plastic, it wouldn't snap close anymore, so I wanted to
ask if there are clamshells that would fit those card measurements? or does anyone have
an idea? Thanks.

[TrekStar]

Those measurements on the clamshell case were slightly off, clamshell case length to fit figure
and card inside is just a tad over 9 inches and the width measurement is about 8-1/4

My custom card back is just under 10 inches length and 7 inches width.
so length to long by almost a full inch and width to small by 2 inches.