If it's your blank fretboards you want to enlarge, just increase the size in the Expression Designer.

If it's all fretboards, JW Change > Fretboards > Resize

Document Options > Fonts > Chord Symbols > Fretboards had no effect. But Jari saves the day, again!

E fretboard resized to 150%:

Thanks. I'm embarrassed to say I don't know where to find JW Change. It's not in the Chord menu and I don't see it in Utilities>Change. Toss me a clue?

It's a separate plug-in. Go to http://finaletips.nu/index.php/download and work from there.

Jari makes these incredible plugins at no charge, but he does accept donations. If you find this or other plugins useful (and you will) donate!

Wow these are great!

However, I downloaded and installed JW Change. When I went to Fretboard>Resize it didn't allow me to Apply. Didn't matter if I selected chords or not, or any filter setting, or the Relative setting, Apply was greyed-out. I'm on the latest Finale version, Mac OS 10.14.6. Any idea why that wouldn't work?

You need to select the staff, not the fretboards. That threw me at first, as well!

Ah yes, that works just fine. Thanks for ongoing help this morning, very much appreciated!