I thought I'd share this, just a pic I had stashed somewhere.

Another option is to redrill the hubs to suit the new stud pattern the rear drums could be done quite easily, but only with larger PCDs like a beetle's 130mmx4, the common 100mmx4 puts the studs too close to the wheel bearing. On the fronts it's possible to machine off most of the mounting face and weld on a thick steel disc, then drill that for the new stud pattern. I've only seen this done on buggy cross cars, whether it would be safe for road use, who knows.