You only need to repair the threads if you damaged the old ones. If you drilled off center etc.... Since you have it mounted in a drill press. go ahead and open both holes up and tap the new thread. A mill would be better because you could power tap without having to deal with busted taps. Next you will have to open up the holes in the base. The new drill will follow the old hole within a .001" or so. a center drill will work for the tapered head screws but the angle may be slightly off. otherwise you will need to find the correct drill and countersink.


The front screw will always be short due to the wall thickness of the action and the diameter of the barrel threads. You could divot the threads but I would not go below the root of the thread.