One of the things the shop manual says is that in order to change the top portion of the seal, the engine has to come out and the crankshaft removed. Many of us have proved that wrong!
In my case, the first two seals leaked badly after about 200 miles. The problem was the main bearings were worn out and the seal was being pounded flat. I replaced the main bearings, adjusted them for minimum clearance and the new seal does not leak at all.
