MaineGeezer wrote:I've never built an electric guitar, so bear in mind John's (Tippie53) caveat about stupid answers, but I think I would be inclined to do a complete assembly first, then take it apart, do the finishing, and reassemble. That assumes everything attached to the wood is screwed on and removable. If wires go through holes and are soldered to things on both sides of the holes, finishing before the installation of those components would probably be advisable.
In my experience, I would not do this. I would make the best effort possible to assemble it exactly once. Why? Because these cheaper kits have screws biting directly into the wood of the neck heel, meaning every time you disassemble and reassemble, the whole thing gets sloppier. Also, do not set it up, take it apart, and expect the setup to be even remotely accurate when you put it back together. That's part of the slop in the joint that I was talking about.
If you take it apart a couple times along the way, it will probably work just fine when you're done -- but you've now burned a couple of the opportunities for future repair before the holes in the neck heel get too chewed up to work properly.
Putting the electronics on is not particularly difficult, whether you do so before or after assembly. It's certainly not worth taking the neck off if it's already attached. It's not even necessary to completely unstring it, just loosen them off enough that the pick guard (and everything dangling from it) can be slipped in and out as required. Personally, I made the output jack attach to the pick guard with push-on terminals rather than being soldered directly, and the ground wire running to the tremolo bridge claw is attached to the output jack's wire so it also gets disconnected at the same time. That way I can detach the entire pick guard and put the guitar aside when work needs to be done on the electronics. (Pic attached.)
Also, you want to shield the cavities and the back of the pick guard. Pros use copper foil tape and/or conductive paint, but aluminum foil tape is way, way cheaper (as in you can get a roll at the dollar store which will cover three guitars vs. $20 worth of copper to kit out a guitar) and it doesn't matter a whole lot as long as the adhesive is electrically conductive. If it's not, then you have to periodically roll the edge of the tape over so there is metal-to-metal contact which you can then secure with more tape.
So, do the finish first, shield second, fit the rest of the parts like the neck and bridge third, and then install electronics last. That would be my advice. Also, spend lots of time and love on the neck -- leveling and crowning frets, taking all the rough edges off -- because that's where cheap instruments show their shortcomings the most. If you can make it
feel good, you'll play it even if it isn't the best sounding instrument. (Then you can hunt for pickups to make it sound better.) I found wipe-on polyurethane works just fine as a finish for the back of the neck. Two coats with a little light (800 grit) sanding in between and after, and it's almost like the poly isn't even there.
My other experiences with kits like this: (1) The pickups are probably going to be awful. Expect to replace them. (2) The rest of the electronics are cheap but perfectly functional. There is no point in replacing anything unless/until it breaks. (3) The tuners are probably going to suck, expect to replace those too. However, if you don't bend a lot, you may actually find the included set to be usable. They're certainly good enough to start playing, but re-tuning every five minutes gets old fast. (4) Sinking a little more money to buy better parts
is worthwhile, because the kit is rough, not bad. If you put enough time and care into it, you'll get a good instrument out the other end -- except for those damn pickups.