I would not use a regular gear puller to remove the pulley. Only a slight deflection and the pulley will wobble and could cause a problem with the belt
Getting it off with the correct puller is easy, I borrowed one from a guy I know, but as others have stated Many auto parts stores have loaner tools for free, just have to leave a deposit
There should be threads in the shaft on the pump, these are to remove/install the pulley
I work at Ford in the area that builds Power Steering pumps. They are really simple and few parts, but what I do is air test them before function test. A small scratch on the shaft or a groove worn into the 40 year old shaft might not give you the leak free results you are looking for.
I have some special tools to disassemble the pumps that leak. The biggest problem is a seal damage when installed or shafts that have a fine line in the seam.
Make sure you have everything as clean as possible when building. Use some light oil to lube the seals and O rings, and NEVER force it together.
I had a Federal pump on my 340 before changing to a March Billet pump when I installed the serpentine belts and pulleys