Where is the best (easiest) place to tap into the Mirage's speaker wires to feed a subwoofer?

I was looking at removing the lower trimpiece that sits between the front and rear doors to see if there was easy access to the rear speaker wires leading to the rubber grommet that feeds the doors. Seems that location would have fewer wires to contend with with - just the door locks and speaker wires.

That would also make for a short cable run to the hatch, where the sub would go. Run a power lead and a ground and it would be done.

Anybody know if the lower piece of the trim between the doors is easy to remove\reinstall?

Secondly, are the speaker leads readily available under there?

I don't want to pull the head unit out.

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