Hey Bill, sorry for the late reply. I'm by far no expert on the subject but I've cleaned and repaired my share of reels and all the advice i've seen on this subject is pretty solid.
One thing you might consider is to remove the shields from the spool bearings and run them "open-faced", (SPOOL BEARINGS ONLY!!) That way the oil you apply to the bearings goes directly to the balls. Of course doing this will require that you oil your bearings more often, but if you're already pulling the spool bearings out to clean and re-oil them as part of a regular light maintenance plan, than this shouldn't be any more troublesome than what you're already doing.
There's a lot of different opinions about running an open-faced spool bearing on a reel, especially a saltwater reel but I've been doing this for a couple of years now and haven't had any problem and I mainly surf fish. My take on this subject is yes, water can enter the bearing but water can also get out because the shields aren't there to keep it trapped in. Like I said before, you have to clean and oil them more often plus it works for me.
Anyway, hope this helps and good luck
rjr