yeh the ae82's have a double negative system or something, so you have to rewire all the speakers Was a biatch of a job, but not hard...
hmmm i installed my sytem in my ae82 and as far as i know it has seperate earths for the front speakers, unless it was behind th dash that they join, my system is running fine and has been for the last year so im guessing its alright
When your were finding your speaker wires did you use a battery to "pop" them?if you did you would find that both speakers would pop at the same time...
Unless some previous owner had fitted an aftermarket h/unit in the last 15-20yrs (ae82)(highly likely...)then they should have changed the wiring.