yeah I think the original you had was 592mm long, the replacement you got is 611.
My 1995GS runs a 611mm belt.
the 611mm belt should easily slip on in place of the shorter belt?
if anything, the problem will be that there is not enough adjustment in the alternator moving "up" to tighten it enough.
you did loosen the bolts for the alternator and let it drop down to remove the old belt right?
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