Oh boy, he's an expert, don't argue Nick!
BTW, any chance you're out at HPT weds?
I learned via a crew member for Dean Martin that Roush (contracted by Ford to actually do the work for them) saw negative returns when they went beyond 2.6* of negative camber on the factory GT500's fitted with OEM hardware (meaning stock equipment).
Feel your pain, I had a customers GT350R at shop aligning last week, I suggested less camber, as mine was wearing inside of front tire and rears were perfect, and he said to max it, he wants as much as possible, customer is always correct. He went off track and tore car up?? Maybe he should have listened, but what do I know. Woops.