Now that I think more about it, you could use a different compressor, as long as you use the lines that go with it. I can't remember which way it goes, but the pressure relief valve on one style was on the compressor, and the other style was on the low pressure line. I ran into then when I was putting the AC back in my '91 that did not come with a compressor. Nissan switched from R12 to R134a in '94, that's why that year is different from '93. The B14 might use the same compressor as the '94, but I've never had to look at both and see if they match up. You could use a B14 part in a B13, as long as you use the lines from the B14. The dryer is different, but it's better to replace those anyway.