The one we just put on a 67 GTO seemed to fit just fine, but it isn't on the road yet. Got it from RideTech because they are local to us in Jasper Indiana. They listed two different sizes and we weren't sure which one we needed, so went there and picked it up in person.
https://ridetech.com/?srsltid=AfmBOo...KiSbRQY9Y1INdo