I have not done a foam seat for my Stovebolt, but on my F250, I've had the seat covers repaired and the foam on that is roughly 4" thick. That might give you a starting point. Get some 3" thick and 4" thick foam samples and test sit them on a piece of plywood. I would make the seats about the same height as the originals.


Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.