I was told this motor was "bad". When I got the truck home, I went to try and start it to see how bad. It fired once. Then fired a 2nd time (priming it with gas). Then it pulled fuel up, fired and ran for a bit once it pulled up fuel. It was making a not so loud clatter. Then all of a sudden, after about 10 seconds of running, it sounded like a big backfire, and it died. Wouldn't spin over anymore.
I drained the oil... and 2 gallons of coolant came out before oil (there wasn't any water on the dipstick when I first tried starting the motor).
I'm thinking a wristpin was the initial culprit. Then when I fired it trying to make it run it must have shattered then.