Remember, your car is 30+ years old now, and who knows what drifters from the 90 in Japan + whoever had the car over the years have done to your car (before trying to return the car to "stock" condition and auctioning it out of Japan + whatever's been done afterwards).
Always pull the parts in question out, measure and investigate. A lot of stuff can be sub'd out (on 90's Nissans and Toyotas), so as a general rule of thumb, pull out and measure then investigate.