So this is my first BB30 frame with FSA Gossamer Cranks and I want to replace them with some Ultegra Cranks I have with adapters but can't figure out how to get these off. I have the allen socket and it breaks loose fairly easy but while unscrewing it, it hits a point where it becomes quite difficult to turn. I don't know if this is normal or not as I don't want to damage the threads or crank removing them. Does the little piece on the outside with the holes around that looks like maybe a spanner would work need to be removed first?

Any help would be appreciated. I went onto FSA's website and under support and looked for documentation for installation for this crank and it says "There are no items in this area."

Thanks!