Note the dark, cork colored balsa. When pressed, it oozes water. Doesn't smell bad though. The white areas are where there was still enough lamination that it didn't pull up easily. Also, the white is dust from cutting the skin. Here note the close-up of the rotted core.
I then used a chisel to take out all the balsa. It came out quite easily. I kept digging until I got good wood, it took several trips back to the garage to cut more skin. The pile to the left is the rotted balsa and skin scraped from the hood. The hood dropped about half its saturated weight with all the crap removed.
Repair will be pretty straight forward. Clean and prep the underside of the top skin, cut new end grain balsa, epoxy it in, then apply a new layer of glass over the repair. Off to the hobby shop for balsa!