Reply to "Looking for passenger car diaphragms and dinning car roof vents"

Scale City Designs, Walthers, Precision Scale and Union Station Products all make diaphragm kits.  Though it sound like you're updating older heavyweight passenger cars I would love to see O scale full width diaphragm kits for streamlined passenger cars.  Union Station makes end plates for full width but curtains are not included.  Union Station should also have the other parts you are looking for.  Check them out.