I am almost certain the harness is not for a 68. 68and 69 had a metal socket permanently attached to the housing with metal prongs going into the harness.
Your are correct, I just figured it out. Will look for a 68/9 for Todd, and re-list this one, I think it is 70/72 but do not know if they are the same, thanks for the catch.
Because of the Plastic Protector that's on there I would say you have a 72 Harness there. . . . (UNLESS somebody added it) Below is the 1970/71 Harness This is the 1972 Harness. Buick added the Plastic Protector in 1972. Other than that I believe you could use it on 70-72 if the "Look" didn't matter. Hope this helps . . . .