Well it is kind of a long stretch on my part, amigo. I was only thinking if your bell housing covered the rear oil galley plug (like the 235 does) and if the bell housing covered it, then it could have taken a while to show up as a problem...your comment about having a large rear main leak and not having one while it was first started made me wonder if a missing plug took a while to introduce itself to you. As I said far-reaching thinking here.
Jon