The Mexican truck didn't have one of these nor did they follow the numbering system from Japan or the US.
Whatever the chassis is, was made by the conversion company that made the truck. I have never seen one like this before although some vans were made from the 720 4 door pick ups that we had.
This is a unique vehicle that should go to somebody that will make it into what it could be.
Imagine a Nissan V8 under the hood.