you need a puller to pull the pulley off of the old pump. any 3-jaw puller that'll fit will work.
ive never looked at the pump on my ranger, but when i did the one on my escort, the new pump came with a nut and bolt that were threaded into the hollow shaft of the pump and used as a press to install the pulley onto the new pump. if your ranger pump doesnt use this setup, then you'll need a press to fit the pulley onto the pump.
if you have other means of transportation, i recommend taking the old pump off and bringing both pumps to a shop. this way they can swap the pulleys over for you and probably wont charge you.