Ok, It dawned on afterward you were looking to make legal barrel length - but you're good to go with a 16. The Noveske is an over-sized flash suppressor for really
short barrels. Black helicopter stuff.
(I could use one for my 10" .223 Contender though.)
I don't use any of the flip-up sights, so I'll let those that do own them answer that one....
As far as tools go, I use an upper receiver holding block for barrel work, but you can get away with a set of barrel blocks that hold the barrel in a bench vice if you are careful not to twist the receiver when torquing it down.
A barrel nut wrench or strap depending on your forearm type, and some pin punches should just about cover it.
Of course you'll have to post pics of your build ya know.