The late 67 AC Control lens is a little different than the early 68 lens. I don't have a lot of info on the 67's, but I believe the Firebird was also different. The 67 AIM doesn't show any changes to either the standard heater control or the heater/ac control, so it appears it was the same througout production. However, I'll see what Daniel and Troy have to say. They're more in tune with the 67's than I am.
The numbers you found on the controls are probably casting numbers for the bezels, but send me the pictures and let me see what you have.
Not a great picture, but here's a late 67 AC control (07B) and the drawing from the AIM.
Edit: I also found an early 67 AC control (10E) and it's the same, so unless the VERY early controls were different, they stayed the same throughout production.