Scott, Wow...another Caravanner, and '57 to boot! Mine has 16 inch wheels. It had Michelin X Radials (7.00 R15 XCA) and I have replaced with Yokahama LT Radial 215 (7.00R15 LT). That set up leaves just over 3" of clearance in front and almost 2" in back. Good luck. Ours pulls like a dream. Bert