Oh, you opened the can of worms all right! So not really up on 67 and 68s, but I think they were both one lever for the kick vent. 69s are different. They came in three (maybe four) versions. First off there was a mid year change around Nov/Dec/Jan. The early 69s got the 'two piece" kick panels, which was basically a separate vent cover but located the door jamb screw lower down. The later 69s got the "one piece" which molded the vent cover in the kickpanel, and located the door jamb screw higher up. These are not interchangeable due to the one screw location. But if you fill and re-drill the hole, they will fit. These both came with two levers, one for the upper and one for the lower.
Now Air Conditioned cars came with a different kickpanel all together. The drivers side had no vent at all and the pass side, the lower vent hole was used for the "max-air" flapper. Both sides got separate screw on lever to control the upper dash vent. There may have even been a early/later version change on these too since the door jamb holes may have been different.
Easiest way to tell is look at orientation of levers, 67s and 68s are more of a slant and only one, 69s were horizontal and had two.
If you have a 69 without A/C, then you have two levers. If yours has a separate vent covers, then you need the early "two piece". If not, you need the "one piece".
Hope that helps!
