mtvoices,
Do whatever suits your tastes. Your truck is so rare and interesting that just about anything would look nice.
Do you know what was the original covering in 1936 and how it was attached? In Advance-Design Suburbans, the rear floor was one piece of plywood covered with glued-on linoleum.
In 1936, was the rear "bed"/floor of a Suburban the same as in a Panel?
Was the rear floor/bed in the Suburban made of wood strips with metal strips in-between?
Was the floor covering rubber?
Was the floor covering glued on?
(inquiring and ignorant minds want to know)
Thanks,