Thanks for the tip. I'll give it a go over the next few days.
I've got a a San Francisco II which won't boot past the Android logo. I've read the guide which is really easy to follow. However, all the downloads point to unbuntuone which unfortuntly closed down in June 2014 which is a shame as it looks like it will solve my issue. Could anyone point me to similair downloads or otherwise advise how as a noob I can get my San Francisco going again?