A great stain job on the neck. You've done some really good fading/blending. It's going to look even better with some clear finish coats on it.
It's a bit late to mention it now, but it is better to leave the parts of the neck heel that need to be glued unstained. You certainly want to mask those areas off before you add any clear coats. You'll want to clear coat one or two mm past the join lines, but no more.
You'll probably need to rough-up the parts of the neck heel to be glued with some coarse sandpaper before you glue the neck on.