I fabricated a REALLY jive tool to remove what passed for speakers on my
nightmare '87 Syncro.  ( It's somehow fitting that the speakers in the car
didn't work either).  I simply pounded two finishing nails into a short piece
of 1" X 2" that corresponded with the outermost ring of holes in the plastic
speaker grill, if you follow me.  I just stuck the nail heads into the little
holes and turned the piece of wood---they came right out.  Hope it helps.  

Matt Q.