Good article.
I have a North Korean AK-47 (my brother-in-law gave it to me to hold when he moved to Kalifornia). I asked my father-in-law if it could be converted to fully auto (for academic purposes, of course), and he said he knew how, but it was a somewhat involved process.
This all got started because it came out that the original MAC-10 could be converted to full auto in about ten seconds with a flat head screwdriver. That was the 1980s and things really went crazy from there.