Chrome air cleaner lid

Quote from Frank Bullitt

I have read that an original air cleaner base for 65/66 are normally date stamped but what about the chrome lid are there any stamping's and are the originals the same as the reproduction ones?

There are no date stamps on the lids. Generally the reproductions are noticably lighter than the originals. The edges of the different shapes of the original lids are noticebly crisper than reproductions. There are indentations in the center of the originals to keep the wing nut from moving as the wing nut will have a ridge to fit into those indentations. Some of the later better quality reproductions have all of these features so buyer beware on them.

Critiques are welcome on this.

-Fred-