how did you get on with your adjustable mounts on your photon? I had the same problem, but not for windage! The crosshair was an inch low of target, so I shimmed it up with a set of Hawke shims off fleabay - plenty of adjustment after that with X=+10 and Y=-12, so the Hawke shims worked nicely!! I did end up buying a set of ATP72 Picatinny adjustable mounts, but unlike the APT66 Dovetail mounts, the Picatinny only adjust for elevation... It wasn't a problem though... I only seemed to need the adjustment on the elevation anyway!! Now sitting at X=+6 and Y= -4!
Hawke shims are about £