From the end cap side, remove the silicone holding the wires in place.

Proceed carefully Make sure the speaker is powered off. Avoid cutting the wires. A plastic ustensil is probably best, or a very small, dull screwdriver.

This took me about 30 minutes and I forgot to take pictures.

Disconnect the AUX input plug and then pull that wire out from under the PCB so it can be aligned with the hole.

Re-assembly Notes.

Push the AUX wiring between the PCB and the chassis.

Plug the AUX connector back in.