Engine repair update: I'm happy and lucky to say that the '97 that I repaired because of a dropped #4 cyl valve seat is quickly approaching 184k miles total ... that's 40k miles since engine rebuild.
The car is back with me (Daddy!) because the ac is out .... looks like a ac clutch coil has opened.
I'll start on it if I can ever finish the second '97 that I'm doing pre-emptive repair to ... before it drops its valve seat. ("Daddy" again!). The wear in this engine has been very nil ... 175k miles thus far... engine internals very clean ... good 'ole MOBIL1!