NOS rs gas cap

[RAfbody]

I recently noticed some differences in the rs gas cap for 1967-68.  I looked at 2 originals that was caste or riveted together, a reproduction that was made the same but  known to be a reproduction and one that I was told is an NOS cap that has screws holding the gas cap cover to the part that fastens to the fill neck.  Could this one with the screws actually be an NOS cap?

[Tinkerr]

yes it could be a NOS cap the original and early GM caps that you could purchase over the counter were riveted.sometime later the GM over the counter caps were screwed together(don't know the date for this).the same is true for the SS caps.i know this because i bought a SS cap from GM  several years ago while collecting parts for my car and questioned this same point(screwed together) its still in the sealed GM bag setting on a shelf waiting to be utilized.the riveted ones usually bring more money.

[RAfbody]

Thanks.  Looking at the one with screws, the crome and other appearances did not look reproduction to me but I wasn't sure.  Thanks for the reply.