Does anyone know the official diameter of the Freelander 2 headrest pole size please?

I have ordered 2 x 9" Headrest DVDs which come with the (rather weedy) 10mm poles.

I assume a beast such as FL2 has much wider headrest poles 12mm / 14mm?

Obviously I dont want the headrests rattling about and so wanted any info folk may have on which adapter to use and where I can best get these (eBay?) - links appreciated...

Also for the wiring, it looks loads easier to tap into the rear cigarette power source rather than remove the whole centre console (and handbrake) to tap the front one. Am I right in thinking that this would then result in an 'always on' power supply to the rear screens?

Not sure I can trust 3yr olds to switch them off or remember myself so that could drain a battery or 2...

Any thoughts?