I have a cocking piece mounted ghost ring on my 404 J - different design, but the principle is the same
That rear facing little screw right below the aperture - loosen that screw slightly and then roll or slide the aperture to the right (I can see that it is currently all the way to the left, which would would make your rifle shoot right). My guess is a little to the right of center would be good starting point. Adjust as needed once sighting in the rifle. One suggestion - don’t bother with targets, a straight dead vertical line at 20 yards is perfect - remember you are now only worried about the wind age accuracy, so make sure you see the line sharp and crisp.