I went ahead and tried to flatten the pickguard. 24 hours later I pulled it out, and it's still slightly damp, so I re-clamped it. I did put it in the first mockup picture before reclamping it, though. I did a few little things, such as getting the pickup mounted on its springs for height adjustment, drilling for the tailpiece attachment and string holes, etc, etc. Lots of little thing to get it to the point that it was playable. The biggest thing I did was slot the bridge for the strings. This went fairly easily, except for the first slot I tried to use a guide which just ended up messing me up. Due to that the lowest string is a hair over a millimeter off from the others. Really nothing I can do now other than making a new bridge, which I doubt I have time for and am not particularly inclined to do. Although it doesn't look particularly terrible, and the playability is just fine, so it's 75% an aesthetic issue. I suppose that's what happens when you rush things. But then this whole guitar is a bit of a rush job.
Anyway, it looks great and plays quite well. You can see where I mounted the strap buttons as well. One on the tailpiece and the other on the heel of the neck. It balances well there and is quite comfortable to play.
Now I'll get it disassembled and finish sand and clean up a few things before I start the epoxy/tru oil finish.
Also, given the possibility that I may have to make a new pickguard, what would you guys do? Would you do one in a traditional pickguard material, and if so what color/kind? Or would you go with a solid walnut guard? I'd love to do one in macassar ebony, but I don't have any large enough chunks.