That blows! I would be inclined to think it's a crack in the block. There's a few techniques to find them, but I'd grab a new block for the amount of downtime it's had.
I usually grab the motor with a hand and use a small hammer to lightly tap the body of it. That was a year ago though. Hopefully, someone will chime in that's done it recently.
Just wanted to share a new site http://www.skfpartsinfo.com/ that lists automotive bearings by the vehicle. These can be cross referenced with other manufacturers too.
Is this sold? (which it appears to be by the photos) My buddy is looking at it on craigslist right now and just sent you a text. Maybe you could delete the ad if it is :flipoff2:
diesel fuel sediment would be the dirt and crap that precipitates out of fuel and settles in the bottom of your tank. I'm not sure that this is what you're looking for.