69 is the same as 68
67 is totally different...there is no seat back catch on the 67 .....68 and 9 have the catch so you have to lift the lever to move the seat back forward to load the backseat.
I have had 67 and 68 seats down to the frame to compare the frames and see if I can cover a 67 frame to appear like a 68/9 and no dice...... the frame is completely different and there is no provision on the 67 frame to mount the later seat back cover, as well as significant differences in the headrest mount area.
66/7 seats are generally easier to find and sell for less but in a 68 it would be "not exactly"