I'm not endorsing what you propose either but...
What you are talking about is similar to what boat guys ask after they have sunk their boats - they all want to know how much tear down they have to do to get the water out. There are several good threads about various techniques that guys have tried. I believe some of them involve using a lot of ATF but don't take my word for it. Try searching for "sunk motor" on www.socaljetboats.com
or a similar site that has 70's style performance boaters on it.
Maybe it will give you some ideas.