A "short shifter" doesn't change anything internally on the trans. It only shortens the distance your hand(and shift knob) moves during the shifts.It does allow for quicker shifts, for sure, but it also requires a little more muscle on your part to move the shifter, since the pivot point is changed on the short shifters.
My thought is it has nothing to do with the actual shifter, unless you just happen to hammer on it all the time.
Chances are there is too much clearance inside the trans, a fork is bent/out of alignment, or the previous "repair" did not get everything it needed replaced.
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1974 Coupe, Multiple NCRS 'Top Flight' 1985 Coupe
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