[morzh]

Arran, well, too late.

I know JB is iron-filled. However I honestly do not see what the problem is. The places where the glue goes are far enough from the place they could cause shorts (btw JB is non-conductive despite the ferric filler).
On either side the drop of it touches the contacts, but does not short anything as it is only one contact it touches. And even if it were conductive, it is no different from the rivet or the contact itself, a long as it touches only one, and it does.

Anyway, I glued it yesterday, and gave it a try this morning. Works beautifully! The tone control does what it says and the radio sounds great! So far the best sounding raio out of the few I have.