I called OPGI and they said they only had them for hardtops and that they wouldn't fit convertibles. Now, most likely the guy is just reading from notes; admittedly, the notes could be incorrect. My knowledge is minimal, so I was hoping someone on the board might have the answer.
The inner and outer rocker panels are the same for coupe & convertible for the 68-72 A-bodies. But they would be a bitch to install without either replacing the outer rockers or the floor pan and braces. Duane