I helped a friend assemble one of the early colonials. We had to drill some of the holes, including drilling and tapping the lock for the "side nails" and installed and cut off the vent liner. The early ones had Chambers locks. The hardest part of the whole assembly was really just getting the brass filed and finished. Another friend built one of the Woodsrunners and said it was super easy, and his rifle came out looking really nice.