Aftermarket radio
There's a company called Connects2 Ltd in the West Midlands. They do all sorts of pre-made adaptor kits for aftermarket head units. They have several for the QQ. It could be this one http://www.connects2.co.uk/Product/ProductItem/CT20NS06 but I'd give them a call, I expect they'd be able to help.
J11 QQ N-Tec+ 1.5 DCi Magnetic Red
I suggest you have a look at Halfords and get them to install the one you fancy for you.