Of course.
But I do notice that I don't need as many diaphram sets as I thought. The archive pictures show many if not most B units without. I suppose this is true of A units as well? I did install diaphrams on several other AB sets anyway.
Of course, both ends and both sides.
I am quite sure I know the ans. but as I am off to my LHS tomorrow in the city for more parts....F7Bs....full sets of hoses both ends? Must be. How else would they fit into ABBA units, eh?