Deleting Unwanted Staves From Score

Hi! I recently created a score, where the first 32 measures had three (3) instruments playing in harmony. After that, the remainder of the score is all in one(1) voice only.

My question: How, or can, I remove all of the unwanted staves from the piece, so the printout will show the remaining lines correctly on the page? Right now, the "hidden" staves are not shown, but space is being allowed below the 1st voice staff.

Thanks!