I posted this over on ML forum just to ask a few people how bad they thought it looked and because I feel like I've been monopolizing this forum with my novice questions.
Anyway, I decided that I need to fix it and now I need your expertise determining what I do next.
I drilled my lock bolt way out of level (a rather embarrassing event) so that the bolt head is much too high on the side plate side. The top of the bolt head (3/8" head) is level with the top of the barrel side flat, as seen in my picture. This is not what I was going for and would bug me for eternity if I left it as is. So, my patching is underway.
My current fix progress:
I picked up a 3/16" birch dowel to plug the stock hole internally. Maybe I should have used a harder wood, but I figured the CA glue should strengthen it quite a bit. I turned down a piece of the dowel to fit the holes somewhat snugly and super glued them in. For making this invisible on the side plate side, I'm going to cut a 1/4" plug of my blank scrap and drill a 1/4" hole where that birch dowel is, then plug it with my maple plug.
For the lock bolster hole, I cut off the threads of my lock bolt because I have an extra and cut it so that about 0.020 or a bit more protruded from each side of the hole. Then I used a couple different sizes of hex screw driver bits and my shop press to press the bolt down into the hole to fill the threads since I didn't have a good way to peen it without risk of breaking fingers or bashing my lock plate into a rainbow. With the bolt protruding just enough, I was able to look between the lock plate and the press plate to ensure I was putting pressure on the bolt and not the plate. It worked surprisingly well and is nearly invisible.
I have plenty of room in the bolster to drill a new clean hole keeping away from the old hole edge. If I do that, I'll have to notch the breech plug bolster instead of going through it. My question is, if I attempt to drill a new hole that cuts into the old hole a bit, is that going to throw my bit way off and give me another crooked hole?