I posted this (link below) for removal of the Mk3 head unit somewhere on the forum. Basically to get at the rear of the head unit you follow the short clip on Youtube. Just one awkward bolt up the side of the head unit to get at all the rest is easy stuff. But some folk have been able to get at the rear by going up through the glove box opening, I never managed it. You are after plugging in the aux cable into the what may be termed as a cd changer port on the lower rear of the unit left side if looking from the front, near the aerial jack conn.
What a coincidence, that just what I’ve done today (tuesday 11th Nov), I found no problem in removing to bolt to the right of the raddio head, just need a extention socket arm.
1)First you remove the 2xside panels under the unit, best to use a paint scrapper with tape over the end, just lever them out.
remove the screws from the left and right of the unit, and those just below
pull out the head, and to the left rear is the socket to plug in the AUX cable.
What I did next was to tuck the cable along the tunnel side and up into opening under the handbrake cover (the cover just pops out).
Next in the front cupholder there is a removable plate i took this out, and made a hole through to the handbrake opening, and threaded the AUX cable through to the holder, then cut a V shape the the removable plate and replaced…and there you are all neat and tidy…
Yes I did something like this ^^^^^ but I fitted the centre console cubby to hold my phone. I’ve got with the Audio-link coupled up to the head unit and sitting in the centre cubby with my music on a USB stick. All working fine, that was until I changed phones, now if I place my phone into the cubby (the reason I fitted it) it intermittently interferes with the music played from the USB. A relocation of phone or Audio-link in the glove box would cure this.