I bought a Snap-on tools years ago, something like 80 buxx, used it already 4 times for ford pumps, it also comes in a casing that allows the removal of more pulley types.
I've open 2 alternators thanks to it. The repair kit, once you have the tool, is much cheaper than buying or let repair. The repair on itself is straight forward. I've posted a complete revision detailed using this kit in my 71 build thread
https://www.7173mustangs.com/thread-fabrice-s-429cj-71-project?page=3.
Most work/time sits into the de-rust paint work. The repair on itself can be done under an hour.
There are few threads on the topic where it's been said you can borrow/rent the tools in many US shops. On this side of the ocean, buying the tool was the best move even used only once as these pumps are not light.
As David said, do not even try without the right pulley extractor. You will break the pulley or damage the shaft. Using the tool, pulley comes out without any efforts.