This is great. you showed important details. I am restoring a John Cooper as well.

I noticed yours is non Harman kardon nor the hifi system model (no A piller twitter speaker). Therefore, this unit should not have any external audio amplifier right? Normally it can be found on the rear panel on the left side. So by adding or upgrading the speaker, does it handle well without the amplifer?

Thanks 😃👍

You don't need to remove the rear seats to get to the rear speakers. kzfaq.info/get/bejne/edSlZZqXyuDDaHk.html