I got a new Green Mtn drop in replacement barrel for my T/C. I had them cut a dovetail for a new primitive rear sight (moved it ahead a few inches). It has two screw holes for the factory sight that I plan to fill with two screws from the old T/C barrel then file flush. I suppose I should put something on the screw threads to keep them from ever backing out. Would Locktite be best? I do plan to brown the barrel next. Thanks. Kirk