Filming dates? Also, other (DVD) stuff

When was TIST filmed? 1982? I keep seeing lots of dates that indicate it was filmed in 1982. I think the date is mentioned several times during the movie like Bobbi Fleckman saying "this is almost 1982!" or something like that.

Other stuff:

1)Quite a few past-and-future "Saturday Night Live"-ers in the movie; a pre-fame Dana Carvey is there as a mime, Harry Shearer (who hated being on SNL), Billy Crystal, Christopher Guest (all on SNL around the time of the movie) and (later) Michael McKean are all in it....

2)The commentary track on the DVD, where the guys comment on the movie as the guys from Spinal Tap, is literally as funny as the actual movie. I'm not making this up--the greatest commentary track OR DVD extra of ALL TIME.

3)Ed Begley Jr. is my favorite minor player in the movie. He looks so hilariously dorky playing those drums. Great move, Ed.

4)My favorite Spinal Tap joke isn't even in the movie. It's in the "Heavy Metal Memories" CD promo on the DVD. They did a song, presumably in the 60s, called "The Incredible Flight Of Icarus P. Anybody." That's gotta be a really obscure psychedelic reference to the obscure 1968 rock opera, "S. F. Sorrow."

5)The deleted scenes: some of them are worth a look. I kinda wish Derek's "Fellini's Roma '79" bit had been in the movie, as well as the hilarious look Nigel makes when he meets David's androgynous-punk son. Oh, and Tommy the limo driver smoking pot, although it makes the guys look kinda evil.