1966 and earlier had those washers. I believe the number to be 6910W and they were used for preload. Big twin and sportster.. Believe the cam adjusting system was still used by turning the bottom cover to get a little adjustment. Good luck
Do not have a picture . But in the harley parts book they show that stuff and if I remember right the lower part will come off if rotated like 1/4 turn after you get the spring tension off alittle. Every thing comes off the bottom. Good luck and be safe the first one I took apart put a hole in the sheet rock across the room from me..