And this

The 1973 TypeLT with the RPO Z28 option is a different model car and never got emblems that said Z28 or stripes. That is all I am stating.

With Type LT the Z28 became a cosmetically latent RPO.

Weird but true.

Absolutely correct! My close friend ordered a 1973 LT Z28. It was a real sleeper because he didn't order a spoiler. The only give away under the hood was the L82 engine, trim tag with Z28 identification and exterior 15 inch wheels. No Z28 emblems just 350 on the fenders.

Hard to imagine that if you ordered a Z/28 in any year other than 1967, that it wouldn't have some visual nomenclature.

The used car dealers back in the day loved getting TypeLT Z28 trade in and only give them TypeLT value.

The 73 TypeLT Z28 is probably the most confusing Z28 ever sold.

There is one other thing that would tell you a TypeLT has the Z28 option, standard full bumper front end has the black grille.

Absolutely true.

Here's a post from a few years ago by Mike Greenawalt here in AZ showing his 1973 Z28's:

Here is Mike's 73 TypeLT Z28 in detail. https://www.youtube.com/watch?v=bI1grhBZWM8&t=316s

How does the RS not require front bumper guards yet the non RS has them?