You might try attending an event, and ask if you can sit in a few different body styles.

I always had a love affair with the '33 Willys coupe, until I sat in a AA/GS with a chopped top! I'm about average at 5-10, 200 lbs, but I had my left knee under my chin, the steering wheel in my chest and my right foot in the passenger footwell.

I simultaneously started having limbs go to sleep, while I was suffering an attack of claustrophobia!

I'm just kidding, but it did remove any desire to build one. The answer might be to build a pheaton, sedan, or delivery body. At least you could push the seats back for some foot room.