Do you have the factory linkages? I dont see how the pedal could go anywhere other than right it the upper part of the pedal, its possible that the pin holding it to the floor has worked its way out, might have a look at that? Any pics?
I'll get some pics posted tomorrow when daylight. Pedal seems to be firmly attached to floor, just keeps sliding off to the left. As far as I know they're the factory linkage.