Call me silly but doesn't the term "Category", whether 5 ,5e, 6, 6a, et cetera refer to the filament and dimensions internal to an 8p8c .... or even a 10p10c modular plug. The exterior dimensions are the same per variety, keyed, non-keyed, shielded, et cetera. Given that, the cable Category doesn't apply and neither do the amount of positions or contacts.
Have you tried terminating on a keystone and use a patch cord? That's common practice.
