Thanks for that link to a brochure on your 2001 Itasca.
Looking at the front roofline, I notice a difference in construction from our 2005. In the 2001 brochure roofline it appears that the roof is a flat one. Ours is crowned. Ours also has a large molded fiberglass piece that overlaps 4-5 inches of the roof's top and cabover's front for sealing of the joint between the roof and the slanted front of the cabover. Apparently Winnebago modified at least it's Itasca roof design sometime after 2001. We do not have a slide, which hopefully will help with wall leaks going forward:
http://www.winnebagoind.com/products/previous-models/2005/pdfs/itasca/05-Spirit-bro.pdfAlso for what it's worth, I disabled our five cabover clearance lights by covering over the holes with a round patch of EternaBond to eliminate any possibility of water seaping along the wires and into the walls when traveling in pouring down rain. I mounted the light fixtures back in place so that it looks as if we still have running lights.