Correct finish for 1972 Chevelle gas cap?
 

Looking to verify what the correct finish is for a 1972 Big Block Chevelle

3rd week March, Kansas Built, has smog and evaporative canister, deep lip gas tank cap.

Looks like remnants of either clear or yellow zinc plating inside of cap but hard to tell.

Thanks

Pretty sure this is your cap a GT73 - it's the deep one.
Outside is zinc inside is dichromate.

https://www.ebay.com/itm/NOS-GM-CHEV...97.m4902.l9144

Yes - thanks. When I did a google search before I posted the question that did not come up. Appreciate the help James!

Same cap that is on my brother's 1973 Z28.

Should be a non vent cap. Have the same type on my 72 Nova.