Figure out exactly where the tumbler screw will fit through the hammer and drill a hole just big enough for the screw to fit through, then locate the hammer on the plate. you will need to be sure that the hammer will land on the nipple. A careful look at a bunch of similar locks will help to find the right location. Drill the same small hole through the plate. and mount the hammer on the plate with a nut and screw If the hammer is in the wrong place, there is a good chance to move it by enlarging the lock plate hole with a needle file in the desired direction. If the tumbler needs to be drilled and tapped do that now. The hole in the lock plate needs to be enlarged to carry the tumbler. The tumbler needs to fit rather perfectly so go slow and get it right. If your drill set doesn't want to play nicely with the tumbler diameter, you may use a reamer. No reamer?, carefully file the hole bigger and use valve grinding compound to get a nice fit. Now you can screw the hammer to the face of the tumbler shaft , it will stick out from the plate but they should swing together. Look at multiple locks until the 'hammer down" position of the tumbler is burned into your brain. The angle of the top or slide of the tumbler should be around 45 degrees below horizontal, mark the position with a scribe. Drill the sear for clearence and lay the sear on the lock plate with the tumbler at half cock. You can hold the sear with a pointed end tap and roll the tumbler to full cock. Go between half cock and full cock until you are sure that the sear catches both notches and no part of the sear dips below the lock plate edge. When you are ready... drill the plate and thread the hole. Drilling the bridle starts with the tumbler pivot and is a lot like shooting with iron sights. When the bridle fits over the tumbler, it can be rotated and marked with a pointed tap, run through the lock plate from the out side. The hole for the bridle mount can be drilled with a thread size drill with the sear screw in place then removed and drilled for clearence. I use sharpie markers to color the plate so I can see all of my little scratches and point marks. This is getting long so when it's time to put the springs in, let me know and I will tell you how I do it.CSW
