Thanks for the response. I'm not at home right now to look, but I don't remember them. I do remember there is a red LED on the left and also a grommet through which I am hoping there might be an adjustment screw or something to access. Will check on this when I get home tonight.
As Gordf mentioned the limit switches are on the left hand side of the screen roller tube. Since your unit was manufactured in 1991 the limit switch are differnet that the ones we make today.
For best results call Stewart Filmscreen toll free at 1 800 762-4999 and ask for Scott Kimber in customer support. He can walk you throught the simple adjustment in a matter of a few minutes.