We have a bin of these. What has been mentioned above falls in line with my collection from Cougars parted over the years. I have a third possible supplier. ASJ
sorry for the blurry photo, looks like KY5DR?
Let me go through some of them again, there may be some 1967 dates with the KY.. marked ones. Some KY.. without dates too, those seem to have the bolts with small washers on them which appear to have been most common on 1967-68?
All of my 1969-70 dated latches (KY..) would have been exclusively from Dearborn. Bolts with larger captured washers, and with a variety of markings on them from these dates.