I've got Glock Steel sights on all my Glock pistols.
One is staked on in front, but when I installed the others in the front I used Blue Loctite. Put it on the screw and let it dry before installing.
The rear is pretty tight and doesn't require loctite. Use a sight pusher if you have access. If not you can use a drift like the Brownells brass/nylon one.
http://www.brownells.com/gunsmith-to...x#.ULE9KIdpcgk
I have one that I flattened the side on so it fits in the dovetail.
Dave