I've had a couple of '40 Ford pu's, I own one now. I am 6' 6" tall-281 lbs, I have more head room in my '40 by far than any of my other cars, new or old. Leg room isn't great, but not terrible..just means I have to stop occassionally on longer trips and stretch the legs, but I do that with anything I own. I have the original seat, which I just replaced the plywood base on. Can't help with the question about the '38's, and '39's.