For my 2 cents the center punch method would be best. But try to space the spots out along the sight to balance out there it will bite along the dove tail. Two divits evenly spaced will give a better bite then a single spot in the center. then put a little bit of loctite red in it. Should do the job. If that dosnt work try the shims.
I know I'm just restating this but the jb weld will chip out if you try to drive in a tight fitting site. It's heart breaking to put a lot of time and effort into getting a good fit then have the jb weld crack and chip out when you start driving in the site.