The head stock has a couple of issues to be addressed. I plan on using filtered compressed air to clear any loose contaminants from the pictured crack then working glue into the joint with a syringe and purpose modified brushes. The punched out area I'll clean up with a router and fill with a well fitted replacement piece. Surface the repair flush with the rear and string channel. I'm also going to blackstrap the headstock with a piece of veneer to hide the plug and add strength.
Again I welcome recommendations, suggestions and insights concerning this repair.