Are you sure it hasn't been modified already. It's been along time since I drove a 58 Cameo, but I don't remember it being that bad and I'm 6'1". I'm not disagreeing with you. Might be a real can of worms to fix. Changing the seat location would be the first choice. There is lots of information on mounting a gas tank under the truck check the archives here and on inliners.org.
Larry
68 C20 327 daily driver
63 C20 292 Camper truck
65 C10 ? Custom Cab AC,PB,PS,$flasher
