One thing, that I had completely forgot - a jack plate. Piece of steel for it:
It's 0.7mm thick, and has enough meat to make 35-40mm, round plate. Of course, I had to test, how it receives copper, once the covering lacquer layer was sanded off.
I have done quite some pcb etching on previous projects, and as a side result, there is pretty much exhausted sodium persulfate solution, that has, I guess, plenty of copper in it.
When dipping a metal part(brass or steel) into that solution, it gets a copper layer. It doesn't seem to work equally on different kinds of steels, and just peels/rubs off, though.
The plate above, it's some sort of soft steel, and the copper appears to stick well in it. As the layer is very thin, when the oxidation of that base metal starts, the copper layer may degrade also, unless sealed with something like lacquer/varnish.
So I'm going to 'copper plate' the whole piece, and then put it in an ultrasonic cleaner(or perhaps heat it), to see how much of the copper remains.
But enough of that babbling. Generally, I prefer the jack plate, that is on the top surface of the guitar body, instead of being in its 'butt'. Also I prefer using 90 degrees angled plugs, as they don't protrude/be in a way, like straight ones do.