The volume wheel will not stay in place because we had to break off the T logo. You need to find something to hold down the wheel, while still having it turnable.

I am sure you can think of something prettier. What we did is:

Find a tiny, tiny screw which will cut its way into plastic

Drill a hole in what's left of the center axis

Reinsert what's left of the "T" disc into the volume wheel, add a washer to hold it down and bolt it down.

Thanks Frank for all your help!