Finally fitted my aftermarket Pioneer stereo in place of the factory fitted setup. I managed to find a harness on eBay:
(Autoleads PC9-410 Active Full Bose Amplifier Adaptor Porsche Boxster Cayman) by a seller called rudiemods here in the UK
This fitted and worked on my Bose setup. I have had to forfeit the CD changer unit in the front trunk but now I have the Bose amp and door/shelf sub working well. So well pleased with the end result. All for £80 too
Make sure you connect up the blue and white wire from the harness in to the remote wire this fires up the Amp and all should be fine.
