Yes, it can be done as described above, or with the use of a proper sight adjustment tool, or find a Smithy that has all the tools and knowledge.
However, my first question is how do you know it needs to be adjusted. Before attemping any adjustments, shoot the pistol off a good solid rest and also have someone else shoot the pistol to see if they get the same results as you.
Very often, technic, finger postion, grip can all affect were the pistol shoots.
Its very possible that some adjustment is nesessary...just be very sure be moving anything.