Issues with supplied 10-32 screws. - Lyman The No. 2 Marlin Tang Sight 3902100

Problem: There are 2 "10-32" screws and neither one had "heads" that would fit the contour (bevel) of the middle hole of the shim part. The "heads" sat above the shim & would not fit flush under the tang. This, of course, caused the "tang" portion not to fit flush over the shim part (like a see-saw). I had to carefully ground 1 screw "head" smaller & also bevel the square area under the Tang for screw head to fit flush (LOVE my Dremel). I then cleaned and re-blued the parts I had grinded. Also noticed the larger of the sights rest on the wood even at lowest setting. I was glad I had ordered a new "10-32 drill & tap" (~$7) & used cutting fluid to help lubricate. Having new sharp cutting tools probably avoided damage from slips plus no "assuming" I had proper drill bit size. "Taps" are strong but brittle and if your not in the habit of using one they will snap INSIDE your project. If you think your going too slow with the "tap" in reality you had better go slower:). *Back the "tap" out alot to clear debris and keep it lubricated. Other suggestions are: no distractions (NO phones, beer, people around), watch YouTube, preplan tools you need, use a padded vise & comfortable chair. OR just pay a gunsmith. **WHICH YOU WILL HAVE TO DO ANYWAY IF YOU DON'T ADHERE TO "MURPHY'S LAW" WITH THIS PROJECT.