Hypothetical question here (Mods please move/delete if inappropriate)
What is the best course of action if someone inadvertently creates an NFA firearm? With an AR, it is as easy as separating the upper from the lower; a shotgun is almost the same, just remove the barrel(s). What if you have something that does not come apart so easily...say an early 92 or 94 Winchester that was converted to a mare's leg way back in the day? Destruction is not an option (well not a good one!). Could/should a gunsmith be able to remove the offending parts or would they be legally and/or ethically required to report?
Again, a thought exercise only!