In most American made Stratocasters and Telecasters “cloth wire” or “vintage push-back wire” is used for wiring. This is braided wire shielded with cotton. Standardcolors for this type of wire are black, white and yellow..
In the well know Gibson models braided shield wire is used. This type of guitar wire has two functions: the isolated signalwire is covered with braided wire wich can be used as ground wire.
Regardless of what wire you decide to use, you might want to consider using heat schrink tubing to cover and isolate solder joints on pots, switches, caps and jacks. Next to isolating it looks neat too.