How to clean a marine band harmonica that cannot be unscrewed?

Here’s a folder containing all the photos that you may want to see

there’s no screws on this one, it has rivets, where you have a machine pressing down on the plate and securing it in its place.

Anyway, I tried unscrewing it, and one of the rivets fell off, you can see that in the pictures, and therefore I cannot take the plate off, I could break it but will never be able to reassemble it. (no music shop sells marine band harmonica in my county) This one is a Marine Band made by Hohner N 1896 key of C.

How do you clean this one?

Marine Bands are nailed together. You can very carefully pry them apart with a pocket knife but you can only do it a few times before the nails won’t hold anymore so they should only be taken apart when absolutely necessary. I’m pretty sure Adam Gussow and Jason Ricci both have youtube vids showing you how to take a marine band apart.

Good advice.
Did the whole nail fall come out, or did the head break off?
If the whole nail came out, just put it back carefully.
If the head broke, that’s a bit more of a problem, but the harmonica will play OK as it is.
It’s only on the cover, not the reed plate. There won’t be a problem with playability.