Changing score (layout) length

Hi,
I know there is an easy, elegant solution but I can’t find it.

I made my score 55 bars and now I want it to be 52 bars. How do I delete those last 3 bars?

Thanks,
Karen

Or use the “Trim Flow” menu item in the Write menu.

Or select and delete those bars with the System Track.

Dude!
Thank you.