The Stovebolt Site Forums The Shop Area Driveline Those dang tire size one more time.

Fronts are 11", rears are 12" and there is plenty of clearance.
Without jacking up the truck and removing the rear wheel I can't
give you the exact ID, but as you can see, there is a lot of room:
http://www.pbase.com/dennygraham/image/161548205

dg