[sdiy] Power Supply

[Moho Disco]

Right at this very moment I'm installing a sample/hold mod into
my Mono/poly.  So I'm supposed to solder into the power supply
at the +15, -15, and GND points.

So I'm looking at the power supply, and I see two green wires
and one black wire coming off of it, and they go into a connector
on a nearby circuit board.  The black wire is obviously the ground
wire, but the two green wires, as they enter into the circuit board,
are labelled with infiniti symbols...?

So my question is, which one is +15 and which is -15,  or does it
matter?

Lava