I got an iK Foam Sprayer (one of the little ones) and some Brake Buster (citrus based, non-acid) to go along with my wheel brushes and pressure washer. The 666Ms are very similar, spoke-wise, to the 788as, so I feel your pain.
The car washing part doesn't take long at all - the wheels are another story, but honestly I don't mind. I find it therapeutic.
