This is what you need if you want to install aftermarket speakers to 
the stock harness:


left front pos = white
left front neg = black

right front pos white/red
right front neg blk/red


left rear pos white/blue
left rear neg blk/blue

right rear pos white/blue
right rear neg blk/white



I received this info from crutchfield and it worked
for me.  good luck

    Source: geocities.com/zx2plus2