Van:
I don't know whether it will help but I have a drawing of a Franklin No. 8 fire door in a 1930 Cyclopedia. I don't know about the "B". If you think it might be of help, I'll be glad to attempt to copy it and mail it to you. I believe that, since it is small, snail mail is the better way to go to retain as much resolution as possible. If you don't want to post your address, you can give it to me e-mail.
Les Clark
cinerail@aol.com