67 4x4 dually

[Spartan]

There's remnants of a 67 I've been driving by the last couple years.
It's a dual rear wheel 67. Yesterday I pulled to the side of the road to take a glance and notice the 4x4 hubs.

My understanding is that these didn't exist from the factory so either the 4x4 was added or the dual rear was added. It has marker lights too. Other than that I don't know what shape the truck is in but judge ing from the weeds around it... For at least 3 to 4 years.

My question isn't do they exist but did the factory make such a truck?
I think not but the memory isn't as good as it used to be.

I did a search but couldn't find the thread I know exists somewhere that says these were/were not made by the factory.

TIA
Spartan

Oh yeah... I'm going to see if I can't pry it out of the guy just for the front axel if nothing else.
Cheers!