I vote heat too. I use one of these cheap blow torches / Cooks torch. It does most jobs. Probably available cheaper if you search t'internet.
https://www.amazon.co.uk/gp/aw/d/B00...jZL&ref=plSrch
...plus I agree that a brake spanner is a must, I'd use one on both sides tho, if you have a pair the right size.