1FM rear speaker change over wiring

[acox99 74 1 Cars]

How are the rear speakers wired in the back of a 1FM as I know that when the acoustic shelf is in the speakers in the C pillars are isolated, and when the shelf is removed, via a jack plug I imagine the C pillar ones work. I would like to replicate this but unsure how to go about it or is there a magic box that does it? 

[jackherer 543]

I've never looked at how a 1FM is wired but I imagine they use a switched jack socket, that's a socket with a switch built into it that is activated by plugging something into it. E.G. https://www.hificollective.co.uk/components/1-4-inch-stereo-switched-jack-socket-gold-plated.html or https://www.gapco.co.uk/Mono-Sleeve-Switched-Jack-Socket.html

[maxi 36 1 Cars]

have you managed to find yourself a 1FM mate?

[acox99 74 1 Cars]

Yes it is a jack plug socket. Managed to find all the info I needed via rob king on the 1FM Facebook page. Steven dean is hopefully going to do an acoustic parcel shelf for me also.