Panel truck carpet question

[68PanelTruck]

Hi guys,
I'm looking for info on carpeting for the cab on my 68 Panel truck. I replaced the cab floor with a new reproduction made for a 69+ Blazer because a Panel specific one is not available. All of the carpeting available is listed for pickups, Suburbans or Blazers.
Question: Will a pickup carpet work? I'm thinking no because pickups have the gas tank behind the seat and maybe the carpet is not long enough to reach the step-up of a Panel truck because of the tank. Or maybe its notched around the tank? Also, the floor of a pickup is a little different than a Panel truck in the area behind the seat. I believe the floor in a pick-up has a shelf that the gas tank sits on and a Panel truck is flat.

Blazer might work but they usually list the carpet for the entire floor including the rear floor and wheel wells. I believe a suburban carpet would be too long because the step-up is farther back compared to a Panel. I'm looking for a carpet for the cab floor only.

So Panel truck owners, What did you use??