Here's the progress 
made aluminum plates here. 3/8" on the rear and 1/4" on the rest. 

epoxied and filled the plates in. 

covered with sticky back plastic and filled with foam. 

so I have solid glass with a plate of aluminum imbedded, I  will drill and tap the screw holes for machine screws later. No wood I used foam to fill the void. I did put a piece of okoume plywood where the bow cleat is. I can get to that thru the anchor locker for backing plates.  

2 layers of chopped glass and should be ready for the final sand 
Posted from my iPhone/Mobile device