I made up a template out of MDF and routed the neck pocket into the body. I had some difficulties, mostly due to cheap router bits and inexperience using power tools, but it turned out well.
I routed the neck pocket slightly undersized so that I could work the neck tenon down to a tight fit. It took me a while to do it but eventually I got a good fitting neck. Its not as perfect as I'd like, but still good. And he neck is centered nicely too!
My maple top was still a bit too thick, so I planed the rest of the top to the proper thickness. The top of a Les Paul as I understand it actually has 2 angles in it. The neck plane sets the neck angle (between 4 and 4.4 degrees), but then the pickup plane goes from the neck pickup to the bridge and is about 1 to 1.5 degrees. I now have the neck angle done, and the thickest point of the maple top. This thickest point is the level my bridge will be at, so I mocked up the bridge and tailpiece to see if my neck angle will be good, and its just about perfect! Next I will plane in that 1 degree pickup plane and route the pickup cavities, as well as smooth out the top contours!
My neck blank wasn't wide enough to make the headstock without gluing on ears so I used scrap that I cut out of the blank. Next I will thickness the headstock, shape it, and install the trussrod. I haven't decided on a headstock veneer yet. I'll update again soon when I have more done!