Why don't you get a class III license - so that you won't have to ask strangely worded and veiled questions about legal vs. illegal configurations on a gun.

I'm sure it's completely legal to have all the literature you want in your house about anything in the world you feel like.  You can probably also own all sorts of metalworking and manufacturing equipment if so so please.

I don't think there's anything illegal about having the capability to manufacture parts that would convert a legal semi-auto into an illegal select-fire weapon.  However, if you do make the parts, and happen to get caught through bad luck - don't expect any sympathy while you're someone's girlfriend for 10 years in the big house.

Here's a (potentially completely irrelevant) observation for those SHTF-types who want to be prepared for anything.  I've spent time in the military (specifically infantry) and have a lot of experience with all sorts of firearms - from M1 Garands and bolt rifles to G-3 and C-7 assault rifles and LMG's.  For a SHTF scenario, I could not care less whether a rifle has full-auto capability or not.  In my experience its use is limited to fighting indoors and clearing trenches - none of which are necessary in a survivalist/SHTF scenario.

For people that enjoy full auto as a hobby and get a class 3, more power to them, but people that imagine they would someday NEED full auto are most likely deluding themselves about the practical benefit.