Oz, I can sympathize with being cross-eyed dominant (Damn my momma for slappin' me)...
Have you shot from a rest to check the zero? If you're shooting from anything under 15 yards, the sights would have to be WAY off to hit four or five inches left, if I'm not mistaken.
I'm in the same boat with my shots, low and to the left, and I'm positive I'm slapping the trigger and anticipating recoil on the first shot of the string, tightening my grip just before the shot breaks.
Give the gun to someone else to check its accuracy, or shoot from a rest, or just disregard my comments entirely if you've tried all this already.