Defender TD5 tow wiring

We've just fitted a tow assembly to our TD5, I'm concerned about the electrics now. The Light skt we bought with it has a nifty plug on the end which sort of made us think that a trailer light circuit was already in place, very well hidden though? I'm happy to do any wiring. My question is, what is the prefered method on the TD5? I Don't want to start chopping about the wiring harness uneccessarily so any help and advice is welcome.

Yes, the socket is in place on the Td5 rear loom. you'll have to delve around in the hole where the loom goes in to the chassis at the back.

Sometimes the plug is "out", sometimes it's stuffed back in the hole, depending on how far the main loom has been pulled through.

It might be covered in tape to keep the poo out of it for when it's not used, so have a dig around.

It just plugs in. job done!