I have only once had to glue up a body blank and that was for the double neck. Everything else I have been able to buy wide enough blanks for a one piece body - they are almost always mahogany and I'm willing to pay a bit more for one piece of wood. I figure that is cheap compared to buying a jointer and all the other stuff I would need for multipiece bodies. However I do glue up a lot of book matched tops (and backs of acoustic guitars). I make the seam with a plane and sand the mating edges with a carpenter's level with double stick sandpaper on it One thing that I did learn about book matched sets is to not sand or plane the show face any more than is necessary - the deeper you go into the wood the more you get away from the book match. Depending on the thickness of the plates I have a couple of methods of doing the actual glue up.