Leaking Richmond T-221 X-fer

[1969K10]

I did a search on this transfer case yesterday, and several of you have had problems with them leaking. I'm in that same boat, did any of you ever get it to quit leaking? This filling it back up every 2-3 weeks is getting old, and the facilities guy at work is giving me grief about the oil slick under my truck. If so, what did you do? I currently have this little one way valve out the top that I've thought about replacing with a hose like on my front & rear diff's.