The skinny elastic I'd been using wasn't closing the mouth, so I upgraded it to little coil springs that I found at Home Depot. Points to the Dreamvision creations website for the idea!

The mouth closes completely now, which leaves me very little space for the ductng I was going to add to guide the suction from the fan to where it's needed...but on the bright side with the mouth closed there's less loss there. (sucking air through the teeth and then blowing it out through the nose is not helpful)

Waiting on the blower fan before I get too much more involved with fan stuff.

One downside of the springs is that they were making a springy CLANGGG noise when they moved, since they were rubbing against the hockey mask frame. I got some plastic tubing (black, stolen from the aquarium parts bin) and slit it down the side, covered the spring with that...it's almost totally silent now, and the odds that it will catch on my facial hair are much less. This is a good thing. :)