I am going to ask a couple of dumb questions.
If I bought this upper receiver kit and this lower receiver, would I have everything I needed to assemble an AR-15?
How hard is it, once you have all the parts?
Be careful. What you’re planning could be considered “manufacturing” for ATF purposes. That’s what led the Feds to invade the Branch Davidian compound in Waco, Texas and slaughter 80-some people.