I've been working away and done the top board. I used a Chinese fabricator and I am pleased with the results, though there were a couple of mistakes I made.
I ended up having to add a couple of jumper wires on the back of the board and I had to very carefully enlarge the holes for the power pins which I had set too small. I haven't been able to resolve the issue relating to GND2 and the Mute circuit so I've ducked the issue for the moment and added a jumper to the board so I can come back to this. I've left the components for this off the board. I don't really understand the purpose of the Mute circuit so if anybody can help I would be grateful. If it is optional, I'll just leave it.
I've assembled the board and tested the power supply. I am using a spare ADA MP-1 power transformer I have. This is a photo of the assembled board.
I am planning on doing the main board next but this time I'm going to double-double-check it before I send it off.