There is also an on-line manual you can refer to if you dont have a copy of the factory service manual. (A highly recommended acquisition no matter what you ride) The site is Goldwingdocs.com. http://www.goldwingdocs.com/index.asp
BTW - I don't know if this applies to the 1800, as we have a 1500. But - The OEM windshield on the 1500 is adjustable for height. The Tulsa is thicker than stock, and because of this the height adjustment is lost. The thing is if it is set as high as it can be set the windshield will slowly creep down over a long time. Once or twice a year I have to pull up. For me, that is the only thing I can find about the Tulsa to gripe about.