Hey Doc, do you ever stop building guitars? :glasses9:
From what I understand, though I've never done it myself......obviously, the ground wire attaches to the back of one of the pots in the normal way, then you poke it through a smalled drilled hole under the bridge base plate (assuming your using a standard tele style bridge, and not some funky TOM unit). Strip back an inch or so of the insulation on the wire, to leave the wire itself exposed, then just screw down the bridge over the top of that. The bridge will then sandwich the wire between the base plate and the guitar body making your electrical connection, with no soldering required.
If I'm wrong, then I'm sure one of the more experienced tele builders will shout. :icon_thumright:
Good Luck.
Jim