I just watched the movie for the first time. Did anyone else notice
that Michael Douglas spent the entire movie eliminating all the dancers
except eight, but at the very end of the movie there were about
50 on the stage? Did I miss something?

The whole show leads up to the final cut of the dancers, which ultimately happened. However, the cuts are ultimately unimportant because the whole show is about the development of the characters. In fact, in the stage production, it's a fairly underwhelming moment when the results are announced. After that, though, the entire cast returns to perform "One" in all its glory which is more of a closure thing than anything else, to see the number they've all been auditioning for the entire time. It's also a clever way to do bows, because in the stage production, bows are done as they come on stage one at a time.

No you didn't miss anything the last number is the equivalent of the Finale of the show with every, so every cast member is in it.

A Chorus Line is based around the London Auditions. Simon Cowell, played by Michael Douglas (in his dreams!!!), et al then go to Birmingham, Glasgow, Manchester, Newcastle and Cardiff to audition the rest of the cast!

Simon

For the stage production if you've ever noticed, Larry wears a tank top with the number '17' on the shirt. A little trivia - Why? Because there are 17 people on the line. So adding Zach and Larry, there are 19 principle roles plus the cut dancers in the opening.