The finish is the hard and long part, unless your going to war with your frets... thats the one im avoiding at the moment!
The rest can be done in a day just about!

Get the pickguard and elecs sorted and wired, as its an ST it all sits on the guard and will just pop in when its all done. Drilling holes is a bit stressful i find... but you just gotta get in there and do it! The elecs in place may help you position it correctly as the pickups will be in their spots and prevent the pickguard from sliding around too much, when your happy with its positioning, tape it down to secure it and drill away!
BUT ALWAYS MEASURE AND TRIPLE CHECK EVERYTHING BEFORE DRILLING. Check the positioning, read the manuals and tips on the pitbull website to make sure there isnt something your forgetting, many things can be done out of order... but a few steps will really bite you in the ass if you rush over it and jump on something else beforehand.

Pop in the neck, doing it now or later shouldnt be much of an issue apart from getting in the way. Once everything is screwed in, string up and off you go!