Have you considered a geared head rather than a ballhead? I don't have any experience but look at something like a Bogen/Manfrotto 405 "
"Designed especially for 35mm and medium format camera shooters who need both speed & precision, the
405 is a great three-way head with bubble levels easily seen in two axes no matter the orientation of the camera. Meaty rubberised knobs can
either completely disengage the gear mechanism for a quick rough estimate of position or offer the finest exacting placement for
even a macro shot[/i]. Cranks allow 360 degrees pans and +90 to -30 degrees of frontal or lateral tilt. "
Add a macro focusing rail and you're good to go ... very precisely..
Andy