there's a special tool that can be used, it screws a metal plate rounded and tight enough to get under the bearing and you use a press to push the pinion out... hammer and some even surfaces may work also, but i like to do things right, you can go to a shop if necessary, they can't charge much...
Yes, you can just go to your local autozone and rent a pilot bearing puller. DONT do the grease method. I think it was $20 to rent and they give you your money back when you return it.
I just did mine last night.I used a bearing seperator and a 2 jaw puller the seperator is tapered so when you tighten on the 2 bolts it starts pulling the bearing immediatly then you just attach your puller and crank it off. the puller I had was too small so I took 2 s hooks and bent them so the top s went perpendicular to the bottom s and that gave me something for the puller arms to grab.but if you have a puller that is bigger than 5 inches you should be good to go. the bearing seperator is on sale at harbor freight for like $11.00.if u dont have the bearing seperator you may not have enough room to get the puller hooks underneath the bearing and even if u can you may end up ruining the bearing.