Not that it matters now, but I've done both - if the bearing was good, I've just peeled the new bearing out of the rubber and installed the new rubber on the old bearing.
If not, that required(in my case) cutting the old bearing apart with a die grinder and then a lot of beating with it in the vice.
A cut-apart inner bearing race makes a good tool to beat the new one into place with such that you aren't damaging the outer race.
It wasn't fun, but I haven't used a press doing it.