Ok,
I've been through this post three or four times since my A/C is a bit smelly unless I use the charcoal filter. I ordered the filters, and an air filter, from our host and marched out to the car this morning ready for a tug of war with the glove box.
First I noticed that the screws had been removed before by the scratches in the green primer on the heads. I removed all eight and the glovebox almost fell out in my hands. It took zero effort to pull it out. After removing the black door/white latch assembly, the pollen filters themselves go in really easily. I reinstalled the black door/white latch assembly and put the glovebox and screws back in. The nasty odor is gone. The old filters didn't really look very dirty, but they sure smelled up the A/C. Anyway it was really easy and the air filter was too.
Sure hope it remains odorless for a while; time will tell.