It's 1992, pretty much the only year it can be.
It's a respray.
Evidence.
1990/1/2 only years of wishbone stays
1990 would have U-brakes rear
1991 would normally have a noodle front mech tube, rear mech tube and headtube mounted cable stop, some of these may be missing)
1992 therefore is the only year left and the rear brake noodle fits in, the cable routing is correct and so does the look of it.
EDIT, I'm sure I've seen this on ebay or one that had the same treatment.
EDIT2, Came with Tange Struts, they 'blizzards' where never designed for suspension, possibly until much later.