I'm going to call this thread complete, save for any relevant updates as they occur. The engine runs well and I'll be checking compression after I put a few more miles on.
In conclusion, a motor rebuild in your garage is entirely possible. You will need time, patience, attention to detail, and a stable life situation. Many times this project got derailed by stuff but I managed to press on through. Given the opportunity to do it again, I would, but only because I am planning to keep the truck for a long time. If the Explorer was just my basic transportation, I would have simply changed the head gaskets and resurfaced the heads and called it good. The lower end on these motors is definitely stout and could have gone another 200k miles without all the work I did. The cracked ring land may have become an issue later on, but does not appear to have caused damage yet.
Update 1: Have put some more miles on. Engine runs well. Oil pressure does not seem to be affected by the Melling high volume oil pump. I do have the true oil pressure gauge mod done, and its readings are the same as before. Leads me to believe my factory oil pump was working well and the bearings weren't leaking any pressure. Power is not up significantly since the rebuild. I did fix a random stumble caused by a failing EDIS module.
Update 2: Only a few hundred miles since rebuild. Tested actual oil pressure since I was concerned about the gauge fluttering. Ford spec is 40-60 psi at 2000 RPM with engine hot.
Another member with 220k miles posted 27psi @ 2000 RPM; I get 50 with engine warm.
Other members with used engines have reported 10-15psi @ idle/600 RPM; I get 31 with engine warm.
Overall I am satisfied with oil pressure. The Melling pump does not seem to result in exceptionally high pressures, but it is a "high volume" pump. I have done the "real oil pressure gauge mod" in the cluster, and it suggested that my pressure was on the low side, but that doesn't appear to be true.
