Easiest access to ground, 12V and ignition-switched 12V in centre console

Hi, folks.

I had one of these https://www.carcommunications.co.uk/car-accessories/ipod-car-kits/dice-auni-150-pro-universal-ipod-iphone-fm-rds-kit in The Duchess (my Madeira Red SV8) but she’s been replaced by The Countess and I want to fit one in her, too.

I originally thought it would be easier/quicker running cables to the boot and splicing in to the wires for the electric aerial but I’ve returned to doing it the way it was in The Duchess. I’m comfortable with removing the head unit to get access to the rear of it, it’s just the electrical side I need help with, because I’ve lost the instructions I got. I can’t even remember where I got them from.

If you click the ‘Installation’ tab, you can see I need ground, 12V and 12V ignition-switched.