I've found catalog errors in Rockauto's catalog before. Since they pull their parts database from the part manufacturers, guess where the errors come from?
In particular, I ordered a replacement gasket for my 2004 Crown Victoria, the one that goes between the tank and the pump flange, because I needed to replace the fuel pump, and what they sent did NOT fit but matched the photo--I got the "correct" part as far as part number and physical appearance. It just didn't fit, and shouldn't have been listed as fitting.
I just ended up re-using the original gasket which was still in good shape.
I'd also like to know why, for a 1984 Chevy Cavalier, one manufacturer lists an ignition module that crosses over to a different AC Delco number than another manufacturer's ignition module. These two ignition modules look identical but fit different vehicles depending on what manufacturer's catalog you are looking at.
Makes me wish for the days of paper catalogs. At least a database error won't screw up what was printed years before.