Maybe someone played with rear mech adjustment screw
Few turns out should sort it I think.
Try to spray some penetrating oil (like WD-40) into shifter trough cable hole,that could help also.
You might be right-on there. I haven't looked it over in detail but I'll check the screws. Makes sense if the shifter is topped out but the derailleur isn't.
That's what I was basing my thoughts on as well but I think the Fusion was also available in 91 and 92 [its not referenced on that site but I seem to remember seeing it in some RM catalog scans as I was researching a year for it - I could be wrong however] The later models are mostly Gripshift and don't sport the same comps. Maybe the frame was made in late 92 then finished and built for a 93 model? *shrug*