I posted details on the gtg site but thought I would start a new post. Class C's are notorious for leaks in the cabover area. I was aware of this so bought a rv without the window thinking this would solve the problem, wrong. I was told the leak had been going on for a years. The rain in the east this spring was overload. The shop called for me to see the damage once they had removed the fiberglass. The wood was like a sponge, you could pull it apart. I had no warning, musty odor or visible damage inside until this spring. Physical limitation prevented me from checking the roof but a friend had checked the roof and saw no signs of a leak. I had planned to have the rv recaulked this year because I thought it needed it.
I hope this helps someone from making the same mistake. I am not sure how often you should have your rig recaulked but I will find out. I would appreciate any advice on this topic.