Vintage P-90 wiring info needed

I have a couple of vintage P-90's that I want to install in a Special. To replace the P-100's

Both of these pickups just have two very thin wires coming out of the pickups. One black and one white. I don't know which one is the ground. And which one is hot. I feel I should know. But, I don't.

Could someone help me out?

That's strange, because usally they had shield braded single conductor, so ground was obviously the brade. I'd suppose the black wire. If you have a continuity tester, or ohm meter, see which wire sends current through the metal underside of the pickup, that would be ground.

Either wire can be your ground (soldered to the braided outer covering of your lead wire.)
The wires are attached to the ends of the spool of wire around those pole pieces.
You have a choice to have hum cancelling or not setup of the two P90 pickups.
You can search this site orGoogle how to setup the North-South alignment of the magnets...and the polarity of your coils.
I use a small stud finder to check magnet alignment...any compass will work.
Checking the coil polarity is done by connecting the pickup lead to D.C. Voltmeter...then quickly move ferrous steel (not stainless steel) object over/across the pole pieces. You will see a D.C. Current pulse. Check to see if pulse is negatve or positive charge.

You may have to flip a magnet and switch the coil leads to the ground connection to achieve your goal.

It's a fun learning experience and easy to do.
:dude: