The effect of shortening a note

Hello. Please can somebody help me by telling me if there is an easier way to do what I want to do?

Scenario: you've typed in lots of music and then realised too late that one of the notes has the wrong value, so you shorten it. Now you have a rest after the note, which you don't want. You cannot "delete" the rest because MuseScore knows that, mathematically, there must be X beats in a bar. So it would seem the only solution is to copy and cut everything that comes after the new rest, and then paste it onto the rest, to shift the remainder of the melody one beat backwards.

I'm finding it rather laborious because I can't select it all at once. I'm having to copy it in stages and having to open a second file to copy and paste onto, etc. Is there any easier way of doing this?

Thank you

Posercom xx