You have to love Twitter for pointing you to great stuff like…
Superior Firepower: The Making of Aliens
This feature-length documentary plus extras, made especially for the 2003 Aliens (1986) DVD release, is incredibly informative with all its interviews with both the cast and crew, as well as behind the scenes footage filmed during the making of the film. Every possible element towards what went into making the movie is included here and gives fans an overload of information to fill their brains with.
Got a spare 3 hours, then give it a watch.