I have a couple of cracks in my rudder. I did this in Lake Mead when I was putting the boat on the trailer and the rudder got low enough to get a side load on it in the shallow water. The lake is down forty feet. Anyway, I have a crack on one side across the bolt hole. The wood inside is cracked. My question concerns the repair. Is the wood part of the structure or is it just a form for the fiberglass? In other words, do I have to go inside to repair the wood before I repair the fiberglass? I was thinking of opening the crack, filling it with glue, and then closing the crack. Also, I was going to bore down through the rudder to insert a couple of long bolts across the crack. Is all of this necessary?