Is a 1972 6 cylinder PS pump same as a V8 pump

There are a couple of different manufacturers for pumps that year, and they made both bolt-on and press-on pulleys. You need to look at both to see if you have a match. I'm sure you will need to swap pulleys regardless, and that can be a pain with the press-on ones. Care must be taken to keep from damaging the reservoir and it's seal in the pressing process.