At one time, you could order your bike from the dealer like you did your car, "ala cart".
I've seen some Huffmans with variations that were not in the catalogs. OEM tail lights on bikes that didn't come with them standard or springer racks, some came with fender ornaments and some did not, I have a bike in a color that nobody else has and nobody can explain it. I know of one other like mine but it is totally destroyed.
I suspect my bike was either a special order or an attempt by Huffy to use up old black paint, an uncommon color on 60's American bikes. It's a '63 model without a tank, with decal headbadges, indicating that it was built in the Azusa, California plant, or so I was told. Perhaps it was left over Penguin paint? Who knows.
I've also heard rumor that my bike could be one of a very limited run of early or late model year bikes, similar to what was done with cars to stimulate sales. I'm unaware of any car, bike, truck, or motorcycle company building special vehicles for such a thing, except for Chrysler in the 50's. Examples of that would be the Silver Challenger or La Femme.
I wish more documentation existed for our bikes...