I am a scrapbooker...
This is sort of a tough question, but I think that even though its a 6 x 6 album and it sounds like (so iam assuming) they will take this and add their photos later? I would cut the mats down to about 4.5x 5.5, this will give them room if they have to cut off more, but a little extra room to crop photos, they can take this home and cut it down to mat the photos to whatever size they need.
Now, what you could do, Is provide them with a sketch of the layout you have planned so that when they get it home they can look at the sketch and see how it is suppose to look... Does that make sense?
You can pm me if you have any other questions. I'd love to help
Ronney