That was a fantastic post, thanks! Lots of great information for anyone installing into a Jetta. Good to see that you took care of the power wire swapping ahead of time instead of discovering it the hard way.

And I liked your stunt with using the rear speaker wires to do the run to the fronts.

I did something similar in my Honda. In the dash, at the factory connector, using the crutchfield wiring adapter, I jumpered the rear speaker wires to the front speaker wires. Then in the trunk, I connected my amp's front speaker outputs to the rear speaker connectors. Then ran the amp's rear speaker outputs directly to the speakers with my own cable. This saved one set of wire runs through the already cramped tunnel between the front and back.

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Tony Fabris