its do-able, i actually abandoned the press for a few of them...the angles didnt work out, but if you are going to go hammer method get a mini sledge aka an engineers hammer, and a bushing bearing driver kit...its cheap and will help a ton also grease the shit out of them.
word of advice when getting the old ones out, burn them with a torch, and use a small knife to cut the rubber around the metal sleeve...slam it out and then use a flat head screw driver and a hammer to get the 2 metal halfs out...clean the inside of the cradle and grease it slam the bitch back together. when you do it, if you have any questions feel free to pm me