[barney911rs]

I was in this same boat not long ago. I was not sure about doing the bearings, so I took everything to a local Porsche guy, and he did the work while teaching the process as we went. He used a punch and carefully drove out the both the inner and outer races in the hub. I'd suggest using a brass drift if you have one.

To install the new ones, he used the old race flipped over so the two edges were lined up perfectly. He said you have to be careful, but it works fine. After getting it most of the way in, he flipped the old race back over to finish the job. The reason for this is to provide a small edge you can use to knock it back out again. Only took a light tap to do this. He did not use any heat or freezing at all on the fronts.

Depending if the ding is on the roller bearing or on the cage will determine if the bearing should be reused. If the ding is in the cage, like Andy said, you can continue to use that bearing.