[DavidG]

The original plywood used in the doors, quarter panels, and tail gate was birch. It was exterior cabinet grade rotary cut hence there are no seams on either side of the panels and no knots or other blemishes. It is available from a number of suppliers according to Google and runs about $80 to $100 a 4' x 8' sheet. Likely an odd thickness like 7/8 would be a special order perhaps doubling that price range.

As it has been the better part of 50 years since I obtained the plywood for my station wagon and I am away from the drawing copies that I have, I cannot confirm that 7/8" is the correct thickness for the panels. Presumably you have enough left of a door or quarter panel to measure the depth of the perimeter recesses in the outer maple pieces to confirm the original thickness of the plywood (as 87+ year-old maple is likely to be less deteriorated than 87 year-old birch plywood). Also, going strictly by memory there is a possibility that not all of the plywood was originally the same thickness.

Copies of all of the original engineering drawings of the wood components of a '32 station wagon are likely available at the Benson Ford Research Center in Dearborn. You will need the part numbers of the pieces for which you are seeking dimensions. Those are listed in the 1932 body parts catalog, which is widely available as an inexpensive reprint of the original.