68. Serial # is AD****. That picture of yours with your buck this year really kicked my search into high gear.
Mine is 1969 and when I saw your pic, my first thought was there is a twin.
Did you intend to scope it from the start or did you try open sight options?
I scoped my rifle first to see what factory ammo it preferred, then tried factory sights and aftermarket options. I did ok with Williams peep and Firesight out to 75 yards from the bench, but when I practiced offhand from different positions I experienced front sight distortion from sunlight angles. I can't make my eyes do what they did years ago, so I scoped it.
