Hello Jack,
Congrats on your LeMans purchase thats a great bike! If you get the time ride out to Sturbridge on Sep 9th for the IMOC rally, there will be lots of Guzzis to drool over! As for your questions you might try EBAY for a owners or shop manuel, I managed to find a nice owners manuel for the Rosso a while back and the price was right.
The tip over valve is a small black plastic fitting in the vent lines which attach to the underside of the tank. You shouldn't have running problems if you have the internal fuel pump the tank will simply build pressure. Before i zip tied mine in the upright position my tank would shink dramatically under the tank suck. Until you get to it just open the cap once in a while, especially on hot days with low fuel level.
Hal
http://www.imocusa.com/rally2007.htm