Many thanks to all, especially David S Poole for his excellent description. I was wrong when I said that my adjustment was as far as it would go in the long direction. In fact it was just the opposite, and after a lot of trial and error, I have it close to where it should be. Although I found it to be a simple adjustment, I also found it to be quite sensitive. An eighth of an inch makes a difference. Thanks again to all for you efforts.
Tom