If you are under the understanding that all "53 blocks" crack in much the same way, I am here to tell you that they don't. I have an '98 that came with a "53 block". I put 175K on it with relative easy use, some pulling but mostly town driving. On the way to work one day in the winter (cold weather) the temp went up to normal within about 2 miles, which was not normal. On the way home it began to smoke white smoke. I'm thinking I lost a head gasket. Next morning it had a puddle of greenish grayish goo under it, coolant and oil. Trailered it to my mechanic, he pulled it and could not find the source. It was an internal failure, not visible externally. I bought a non- 53 block recycle engine for $1800 and it is still running on that engine. 53 blocks are a ticking time bomb. If you can do it, get a different block.
DClark
In the hundreds of pages I've read on the 53 you are the only one I have ever heard that cracked internally sure sounds like the wrong diagnoses to me