What if, rather than tubbing, you flared the fenders instead? Something along the lines of the Porsche Carrera 4. This idea came up over a pitcher of beer the other night, while figuring out how to fit the biggest possible tires on the rear of the II. Here's the thought: cut out the curve of the rear fender well; bend a piece of, say, 1.5" pipe to fit the curve; cut a track in the pipe and slip it over the cut edge of the fender well; fair it in with copious amounts of Bondo; paint to match. Fill it with a 315/60, and it's still street legal. Where's the flaw in the plan? Seriously.