I would start by drilling the flint cock so that the f-c screw will just slide through. Position the flint cock on the lock plate so that the stopping shoulder is in contact with the plate bolster. The hole in the f-c should be in the middle of the plate. if it is not, adjust the angle of the f-c shoulder. Once you are there, mark the plate for the hole that matches the f-c. You can use a marker to color the plate and use a tap (with a pointy end) and gently make a mark. when you like the location of the mark, center punch it and drill the same size hole as the f-c. Get into the habit of rotating the center punch as you make the mark, this will even out any out of roundness on the punch. Drill the tumbler for thread size and carefully thread the hole, Turning the tap 1/8 0f a turn or less at a time. If you get any inordinate resistance, heat the tumbler to 900 F and cool very slowly. The tumbler hole is the most difficult thread on a lock and, so take your time and pay attention. When you have the threads, you can stack up the. flint cock, lock plate and tumbler with a try screw. Position the f-c in the down position and rotate the tumbler down as much as you dare. Look at a lot of pictures and compare the spring slide with other locks you have. Unless the f-c came with the square hole cast in, now is the time to to mark it. Take (make) a small hook scribe and scratch the square of the tumbler onto the inside of the flint cock. A whole book could be written about lock design and construction but the second most important thing to study is the position of the sear screw. With a pointy tap, hold the sear onto the plate and let it engage the half cock notch. Watch that the lift bar doesn't drop below the plate edge. while holding the sear in place with a tap, rotate the tumbler to full cock and watch the lift bar. If the f=c is at a reasonable angle at full cock you can mark the sear hole and drill it. All of the other holes can be located in a similar way, but look up Dave Person's method for drilling the frizzenn hole, it works. If you get stuck, let us know and we will get you unravelled.CSW
