you're doing fine mate, take your time.
Don't put too much stain or sealers etc on the neck pocket, or on the neck where it joins onto the guitar. It can effect the take up and adherence of the glue - raw timber is best.
Ah, I see it's a bolt on, no biggie then, but leave it thin, as you have it now is fine. Remember especially for set necks (glue in) though.
Nice job, it's going to look great