Same Sex Civil partnership - EU Non Spain Residents - How to get a residence?

Hello

Me and my partner want a same sex civil partnership near Barcelona. We both live in the UK. We were told that at least one of us should be Spanish resident and have an associated residency (they did not say for how long you should hold such a permit).

Does anyone know of any ways around this? Somesone suggested getting a friends address there and proving you have funds etc (but dont have any friends there!). Any suggestions?

Thanks