pressure plate
I have alway had the stock diaphram in mine. Never did have it stick to the floor, but always shifted at 5000, maybe that made a difference. It is still the original pressure plate, but I have replaced the clutch disk three times since 64.
I just bought a new pressure plate/clutch and went with Center Force this time. The engine is not back in the car yet, but will let you know how it works when I get it going.
Ron