Jim, what would it take to convince you that the 3H code either refers to a previously undocumented stamping or to human error or to simple lack of a the correct letter in the die box, rather than to an option that is clearly self-contradicting?
Recycling/reprinting bad information does not make it any more correct.
I will contact Jim Mattison and publish his reply in full.
Vikki 1969 Goldenrod Yellow / black 400 convertible numbers matching