Good news and bad news on the build front for this.
The good news is that my wooden blocked glued on successfully, I pulled off the clamping dowel from the double sided tape and I then drilled a small pilot hole in the strap button position. This is the block inside the guitar and you can just see the dark end of the pilot hole amongst the lighter double sided-tape residue. I also managed to keep the strap block up against the heel block, so that it has a glued surface on two sides.
The bad news is that all hopes of getting the sunburst finish back on this guitar have gone. I tried to patch things in with some yellow lacquer, but that stayed much lighter than the original colour, which had a touch more orange in it. I wasn't interested in the edges, as they would have been dark tobacco, but needed a clean centre section.
So I mixed a very small drop of red in with the yellow, and it came out a lot more orange. I could live with that, but it still didn't blend things in and in some ways it just made it worse. In addition, in a couple or areas the wood grain of the surface veneers has started coming away, so they'll need filling. So the guitar will become black.
Which would be OK if I could get hold of some black nitro, but Rothco and Frost, my normal source, had sold out of all the tins and only had aerosol sprays left. It has to be black, as I've got gold hardware for it, including an expensive Allparts trapeze tailpiece.
But in looking for retardant thinners, I've just discovered that Northwest Guitars has some, along with those retardant thinners, (which are necessary for spraying nitro when it's hot). So I'll grain fill the top today, ready for the paint when it arrives tomorrow.