Here is what I did with the mono dash speaker. I mounted 2 four inch drivers in the original speaker frame. A little bit of work required but sounds much better than the blown factory speaker. An air die grinder with carbide bit works good for removing the unwanted metal. I cut a 6x9 speaker spacer into 4 pieces and glued it on top to replace the factory cardboard one. Click the thumbnails for full size pictures.

More project photos coming soon!