The late Hawken rifle is a good example of the single lock bolt system. I do a similar technique to David and Dennis in that I inlet the lock - it can only go in one place - until it is almost bottomed. I then tap drill the bolt hole in the REARMOST AND LOWEST POINT in the thick plate bolster. On a Hawken, it's a 10 x 32 cheese head machine screw. Before I thread it, and running the drill bit through the plate's hole, I set up the rifle with the lock in its mortise square with the world in a drill press vise, and drill right through the stock out the other side with the tap drill. Then I pass a clearance drill through that hole, removing the lock plate first. I put the lock back into it's mortise and thread the plate from the offside. Now the lock retaining screw can be used to pull the lock into its mortise more solidly and squarely, and the finishing inletting can be done. When the lock bolster is seated firmly and evenly against the side flat of the barrel, I'm done.