Now that a few hours have passed, I'm a bit calmer. I'll pull the motor Monday (unless I can squeeze it in tomorrow AM) get it on the stand and see what it looks like.
Allegedly, the motor was built by a reputable Jeep shop in Las Vegas? Reno? If so, but the previous bonehead owner munged it up, the expensive bottom-end may still be good, in which case it may not cost a lot to make work. I have a mike set and basic engine tools so I feel competant to tear it down and inspect.
The leaking of juices was so stupendous, it has to be a head tossed on the block to "look good" for dump/sale. I can't imagine a crack, split, or other problem so severe that wouldn't have some sort of external hint. If it is broken hard parts, I'll take photos.
If the head's bad, I can find a head. if the block's bad, I'm screwed, and may look for another solution other than refresh/rebuild.
All's not lost though, motors are replaceable, and the chassis has hundreds of hours into it. The wiring is solid, interior nearly done, glass remounted, insulated, all new suspension, chassis painted, etc. Engines are easy to install.
With all the talk of high-mileage V8's I suppose I should consider it if this motor is totally lunched.
Another possibility is obviously a 4.0. I don't know why I'm hesitant to drop one in. I'm not afraid of the technology so much; it's that old engines are far more beautiful and pleasing to work on. Performance isn't #1, but mileage is, so I suppose I should re-look at it if this 258 is NFG.