Just another thought... and I don't know if I would want to do it to a set of orginal 10" campy's but could you have the wheel machined to change the offset? Of course you would need to make sure you don't hit anything on the inside of the fender well when changing the offset.
Or maybe a little of both. A slight machining of the wheel and a little body massage doing a little less dramatic push on the fender. Just spit balling.