(Are there two threads on this? I think I responded earlier but don't see it atm...)
To get the old bearing off, use two flat head screw drivers under the bearing, one on each side, and it should be easier to pry them off without damaging anything. Be aware this will trash the bearing if it isn't already.
The pin will likely come out of the bridge before the bearing comes off the pin, but that's ok. Once its out, you can put the old bearing on top of something with a hole in it (so the pin has room to come out) and then carefully tap the pin out with a hammer and nail set.
Check the hole in the bridge where the pin goes for any debris, carefully clean it out. Replace the pin.
Make sure the new bearings are shielded, but not sealed. The sealed ones are a bit too stiff. Also, try not to drop them.
When installing the new bearing, press carefully on the inner course to get it onto the pin- two small flat head screwdrivers or a very small socket or nutdriver can work great here. Don't push on the center or the outside edge- you can trash the bearing that way. Make sure you don't press on the first bearing when installing the second too, so you need to support the edge of the bridge with a little creativity, but ideally it won't take too much force to get the new bearing on.
Don't lube the bearings, you'll just attract stuff that you can't clean out later.