I was at GM Nationals at Carlisle yesterday and noticed that the round Pressure relief valve under the Master cylinder was different on the 67 camaro's than the 68-69 camaro's. Is there a difference or is this a aftermarket issue. In all the parts catalogs, they list only one valve and state for the 67-69 camaro's. What is correct for the 67 camaro, big block, drum/disc car. Does anyone have the correct one for sale? thanks Pete