Since Tom mentioned it, the "Half Raven" system is what i settled on for the RV-3 to keep the oil from ending up all over the belly. I really tried hard to convince myself that one of the air/oil separators would do the job, but pretty much knew all along that it wasn't going to cut it. the price of the Raven tank and sump fitting was not that far from what I was going to have to pay for a reasonably-sized separator, so I decided to do it right.
Raven was GREAT to work with BTW!
Paul