Removing a stubborn Wimberley Head

I've had my version 1 Wimberley Head on my 1327 tripod since about 2007.

I'm trying to remove it for the first time and its been a real bear to say the
least.

Any suggestions/hints on removing it?

Thanks
Doug

Back to bolt out from the bottom of the tripod head with a wench and socket or use a rubber mallet to beat on the arm of the wimberly the first option is best the second one will also work I have used both in the past.