I have a featherweight box that WAS full of mold and stunk!! I tried many different methods and I think I have it licked now. I did a search online and what worked was to wash it with warm soapy water and rinse with warm water. I used Dawn dish soap. I then put it out in the sun and let it dry. Then I wiped it out good, all the corners, with a a 50/50 solution of white vinegar and water. Then I put it out in the sun to dry for a week. I brought it in at night so it would not collect dew during the night. It has been stinky free for a week now and I have had it in the house. The article also suggested to put a couple of little silica packets that come in shoes or purses etc, to keep it smelling good. This I have not found yet but will use them when I find a few.
The manuals were also stinky and the suggestion of putting a couple of fabric softener sheets in between a few pages. Put them in a sealing bag and let them sit for 4 days. this has helped big time but not all the smell is gone. So I have just left them in there. not hurting anything and the smell is going away.
In the article I read it mentioned that putting the article out in the sunshine was the best thing. for some reason the sun rays helped kill the mold and mildew smell. Sunshine is free.
Good Luck