I have a Cannondale Synapse. When I back out the 10mm crank bolts up against the collar, the collar starts to unscrew and not allow me to remove the crank arms. Should I hold it in place with a spanner wrench and turn the crank bolt or should I get an extraction tool. If the answer is to get an extraction tool, which one (Park Tool) do I need? I'm exchanging the carbon compact drive for standard Hollowgram cranks.