Last two, 2d Going the other way, presumably down stage (3, 2) - T - N
I think it is PUT ON, NOT UP backwards, but if it is it's a poor clue to me.
20a How to make join a stringed instrument (5) B - N - O Presumably it's BANJO, again a poor clue. Can someone confirm for me, please?
Thanks Bibblebub. I've just submitted and they were right, as you say. Someone commented that 2d was a gem, but I don't think so unless I'm missing something.