The real question is how much are you really saving by doing it. It's a lot of extra work and adds risk of more dust and scratching. I recommend ready cut film when possible unless you see huge cost saving and need it. proper thickness cirkut film is on a 120 thickness stock and not the best choice for 8x10 from a thickness point of view. On the other hand If you do go ahead and find info on a cirkut film source let us all know.I'd be curious.
Jamie