Anybody knows how to remove drivers of Franco Serblin Accordo?

Hello everybody 

Need to replace old drivers of Franco Serblin Accordo speakers due to damage.

But, after removing those screws, it seemed still very very difficult to remove the drivers including the tweeters and the woofers.

Any other fixation which must be loosened?

Anyone has experience with this so can share some tips?

Thank you for great help!