I would like to ask for assistance in identifying the correct 6x9 film back for my newly acquired Wista Rosewood (am not sure of correct model, pictures are below), I think it may just be called the Wista Field 45, it does not have the graflock, the glass back has a slot at the bottom and two "clamps at top, ....I would be awfully grateful for any assistance offered....as it os a expensive mistake to buy the wrong one.......Thank you in advance.....Lee
