I believe there are two thicknesses of drive plates I believe, for stack height adjustment purposes. That probably the A and B . Some clutch kits include a wavy plate, neither A or B , for quieter operation. When doing the quiet clutch mod you must adapt the instructions for you own specific stack height, otherwise you won’t have the correct clearance at the clutch rod. If I remember correctly only one extra plate is involved. I don’t remember ever seeing any instructions specifying two extra plates. Pick one set of instructions and go with it, don’t try to invent some hybrid method for doing the quiet clutch mod. You’re obviously confusing yourself. You sound like someone who is not comfortable doing this type of mechanical work.