If you think it will come off without difficulty you could also clamp it in a vise upside down and take a center punch and put a few dimples in the base. Your creating high spots so it takes up more space in the dovetail. While it's out you could also gently take a brass hammer and give the top edges of the dovetail a little tap.
Doing this in addition to GB's locktite should anchor that sight for the long run.
Locktite alone would probably hold it but a little mechanical edge might be a good thing too.
In Memory of Paul "Dietrich" Stines.
Dad: Say something nice to your cousin Shirley
Dietrich: For a fat girl you sure don't sweat much.
Cue sound of Head slap.
RIP Muggsy & TMan
"If you are a warrior legally authorized to carry a weapon and you step outside without that weapon, then you become a sheep, pretending that JOCKO will not come today."