There's fixing the problem, then there's covering it up. It may be a pain, but it's less of a pain than any damage that might be caused by doing the wrong thing. Pull the engine and replace the rear main seal to fix the leak, would be my advice.
Here's a $15,000 example of why transmission fluid isn't supposed to be used as engine oil:
http://forums.pelicanparts.com/showthread.php?s=&threadid=83967 Gives weight to the old addage, "more money than sense"... :o
-Boyo
