add a top staff to grand staff

How do I add an extra treble clef on top of an existing grand staff, so that I have New Treble/Old treble/Bass?

I saw a forum post on how to add a new clef at the bottom, and that works well:
- Select instrument
- Add staff
- Change clef
- Extend bracket downward

However, I can't copy that system because bracket apparently don't extend upwards. Or at least I could not find a way to do it.
As an alternative, I tried to add a clef at the bottom, extend the bracket downward, then move the new staff to the top position. Unfortunately, the new bracket exits the brace when it gets to the top.
Eventually, I resigned myself to copying the notes---is there a better solution?