I have done a number of bearings and always use the old race to install the new one. When doing so, put the older race in the same configuration as the old one, with the thickest end towards the hub, striking the thinner end with a hammer. (This configuration is important, as it facilitates removal with a hammer and chisle later. If you put the thin end in first, I'm not sure you would be able to remove it). You can put a block of wood over the old race and hit it in the center, or just strike the old race directly, alternating sides as you go. When the new race is all the way down, it will be obvious by the sound and "feel".

Bill Mattson