Is the rocker panel molding the same for 68 Firebird and 68 Camaro?

Nope.

P/N 3904540 (Group 8.304) is shown for "67/68 Camaro" in my 1968 P&A 34 (Parts and Accessories Catalog). Then, taking that number and looking it up in my 1971 P&A 26 (Dealer Parts and Accessories Price Schedule), it shows this P/N as being used for Vehicle Code 5, which is the Chevrolet Motor Division. If it was used on both Camaro's and Firebird's, the Vehicle Code would show both 5 and 3 (3 being the Pontiac division).

So it looks like the 'Bird used a different part.

Ed

I am looking for instructions on how this molding is installed. My 67 RS/SS had them removed and I would like to replace them. I purchased reproductions, and they came with the mounting brackets, but no instructions. I must have been getting tired, because it was not obvious on how they attach to the mounting braket. Any help is appreciated.

The first thing you should do with the repo is round off the top corners at the ends of the mounting bracket. Use a file. "Top" is the taller of the two channels formed into the bracket. Mount it on the rockers with the taller channel up. Carefully slide the molding into the bracket so that it is fully engaged along the top. Once in place, work your way along the molding gently pushing down along the top while pushing the molding against the rocker to snap it over the bracket. In my experience with these the holes in the repo molding will not align with both holes in the car if the front fenders were not replaced.

The repo molding is softer than the original. That is why it is important to round the top bracket corners. As it snaps in place the bracket corners may form a peak in the molding if not rounded.

Thanks for the help.