There are many concerns and challenges in the process, but for me, the most critical is the neck/body joint, both getting a good fit that is also in linear alignment with the body, and getting a nominal angle for alignment with the bridge. Several critical concerns all wrapped up in one step of the process.
There are constellations and galaxies of difference in the complexity of building an "F" model as opposed to an "A" model.
Maybe I should have just said there is a lot of difference.... both in complexity, and time spent.
There are some good books out there that are both comprehensive, and will do a good job of guiding you through it.
My wife says I don't pay enough attention to what she says....
(Or something like that...)