Let me add my 2 cents worth in this debate. First of all I am not taking sides just adding my opinion. I have numerous original pamplets, red selling fact book, a original March 1967 Car & Driver and a March 1967 Motor Trend which both feature the 67 Firebird on the covers and is the main story.(These are original and in mint condition). I also have a GM original brochure titled "The Magnificent Five are here/the Pontiac Firebirds". Everyone of them indicates five models of Birds. Firebird with 230cu, Firebird Sprint 230 cu 4bbl, Firebird 326 with 2bbl, Firebird HO with 326 4bbl, Firebird 400.

Every decoding book or site that I have seen for 67 only does not have an "H" option for the 3rd group of letters. They all show only three choices for that group B=rear window deforst, F=400 option and J=custom option. Could you have mistaken the H on the one you saw as a worn out B? Here is one site the decodes 67's http://www.firebirdgallery.com/67codes.htm