well the panel examples i have found with plank type floors have had side vents. suggusting pre 51, two in junk yard around here both 47 and one i have (49) all had planks. the plywood type floors have all been in 53 panels 1 gmc and 1 chevy i have and 2 that owners were kind enough to let me crawl under.
as far as burbs go, all i have ever seen had plywood.a whopping 2 so i dont have agood clue about those.my guess is tho ,that as much a pain as it is to refurbish i dont imagine many an old owner took the time or effort to change it to a new or different type of floor. but then again i dont have a clue either.
tom
