I've never seen a set of early (67-68) Chevelle disc brakes before but saw these on a very restored 67 and was wondering if they're 67 or a later conversion? The owner was so busy with 5 or 6 other folks prepping the car for a show that I couldn't get a chance to corner him and find out.

http://www.chevelles.com/showroom/396guy/discs.jpg

Only the rotor might be original. It looks like it could be a 2-piece style. I think they quit making them like that in 69 or 70. The rest is definitely not from 1967. They used 4 piston fixed calipers similar to Corvette in 67-68. The locating groove in the rotor I think was used into the 70s even on the single piece cast rotors.