w123 300TD rear speaker wiring route
 

I'd like to tap into the rear speaker wiring for my 1981 w123 300TD. It looks like at the rear the speaker wiring is in the headliner. I'm guessing it runs up the c-pillar covering into the headliner. Before I start taking trim apart I was wondering if anyone knows from experience whether the stock wiring runs down the passenger side of the car or the driver side. Or are there speaker wires running down both sides?

Thanks

IIRC...many years ago...on my 85 TD they all ran on the driver (left) side.