really,
clutches are different and made by different manufacturers,if u fitted an identical clutch,it wouldnt need any adjustment.
when NISSAN built the cars ,they were designed to be fitted with a standard clutch,not an aftermarket clutch.fitting a spacer is make shift no question,ideally if your able modifying slave cyl rod to be adjustable is the way to go,but if your not equiped to do that a spacer will suffice.