I sanded the back after it came out of the clamps, laid the guitar body down on it, marked it with a No.2 Ticonderoga pencil (very important) and cut it out on the bandsaw. I sanded it with a drum sander.

 

I chamfered the edges of the tail block and head block with a sharp chisel and hand-sanded everything inside, just so it’s nice.

 

 

Then I glued it. If the surface is dead flat, it doesn’t take much clamping pressure to mate it up.

 

I laid this big heavy tabletop thing on it and micro-slid the sides on the back plate until it was exactly where I wanted it. then I added just enough clamping pressure to get consistent glue squeeze-out all around. It’s a good visual cue that clamping pressure is even. If there’s a lot more coming out in one spot and another spot is looking dry, it’s a sign of a problem. You need to pay attention to these things.  In this case the ribbon of glue was consistent all the way around and left me feeling good.