My money is on the 1LE = Z28. My memory sucks lately but I'm recalling that the 1LE designation was an 'option package' you could get on some cars. Am I on the mark with that? With the exception of '69, Camaro has had the flat Camaro, RS, SS, and Z28 designations. I'm looking at images of the 1LE and I'm not seeing those characters written on the car anywhere as does the RS, SS, ZL1, and previous Z28s. I also don't recall a 1LE in the historical lineup for Camaros as a proper designation. Just saying...
I like the idea that the Z28 could be a lighter weight version of the 1LE. That would be quite an improvement.
LS - Luxury Sport
LE - Limited Edition (typically changed where it sat in the lineup depending on package - in this case it should be below the SS in this list)
LT - Luxury Touring
RS - Rally Sport
SS - Super Sport
Then you had the Z28.
Does that make any sense? Shrugs.
My thoughts are more based on car names in the GM umbrella. I remember my father (GM Exec) bringing home a Buick Regal that had a mohawk which had "3.8 LTR TURBO" as a promo vehicle. The next year was the year of the Grand National. Remember the Pursuit followed by the Pursuit G5 followed by G5. Grand Am -> G6. Montana was a package version of the van (and memory is failing yet again on the original name of the van), soon to be renamed to Montana. I'm thinking the 1LE is a promo package which is gearing up to be the Z28.
I'd like to think it's an educated guess.
(Note to GM: Humour me)