Hey POGgers,
A guy stopped by the coach the other day and showed me this window extension. First let me say that every window in my bus opens, and ventilation is very important to Janet and me, so this got my attention right away. This little piece is made of aluminum, slips on the end of your existing window rod (opener), and rests in place the same way your existing rod does. It makes a 3 segment widow rod into a 4 segment rod, and the window will open about 4" more. It's ideal for older vintage XL's. I bought 6, and he says he has about 30 left. $8.00 ea., I can get them from him and bring them to OKC, or you can pay postage and I'll send them to you. Let me know.
(The window photo here shows the difference in opening, two with one without)
Ken