[Baron Von Zeppelin]

If it still has the Cloth back seat you might get lucky and find the buildsheet in the springs - if someone hasn't beaten you to it.
That would tell more specifics (wheel type) and match up with the PHS invoice.

I think 4wdb required the 8 inch wheels even when it was ordered as separate option from WS6.
But it probably would have been the "turbo" style wheels on an 81 - i'm guessing.

The rear axle has probably been swapped for a beefed up unit with competition gearing.

Very altered car - leaves you an open book for any alterations you want to make.
You can even buy a new reproduction trim tag for around $300 if you wanted it to go back to the PHS Invoice Car in a restoration.

Looks like a great body for a NY car.
Congrats and Enjoy