Did you adjust the valve lash with the truck running or just get hot and shut it down?
Cold, I can't remember if the TM's say to do it cold or that it doesn't matter, but I knew it wasn't hot, so I did it right after the heads were torqued, while the injectors were still out, so it would be easier to turn over.
Were the freeze plugs common sizes?
Yes, the cylinder heads take 3 different sizes, 3/4", 1" and 1 1/4". Looking at the Dorman catalog, it appears there are basically short and tall versions of each diameter plug. I used the short as that's what the engine had and they were original (still had the green paint of them). The Dorman Part #'s are 555-012 (3/4"), 555-018 (1") and 555-024 (1 1/4"). Dorman catalog here:
https://www.dormanproducts.com/catalog/hardware2006/127-130_Sec8_Part1.pdf
Is electrolysis the culprit?
No way of knowing for sure, but due to the condition of the other plugs and the relative newness of the plugs (the oldest they could be is about 18 years), I actually think cooling system "sludge/debris" collected behind the plug. If you knock one of those plugs out of the end of the 465 head, you'll see that the hole is approximately 1", but that about 1/2" in, the diameter necks down to about half that. Not sure why (perhaps at one point, this was a "stop" for freeze plugs to be pressed against?), but in the end, I think it is possible that the trash floating around in a coolant system can collect behind the plug and cause it to rust. All the other plugs in the heads looked fine, but the end plugs (i replaced all 4) were decidedly worse in condition than the others.
Does freeze plug material type matter?
A lot of folks prefer brass, but all I could find in stock was steel and I was in a hurry, so that's what I went with. Steel should last at least 20 years, so I can live with that.
In the future could you just use a boxed cat's paw wrench with an extension for the cyl. head nut? Or if they don't make a boxed cat's paw, just buy a regular one and a box wrench and cut em' up and weld em together.
Don't know, it is a tight fit in there. There is not a lot of room between the wall of the head and the nut. So much so that you have to wiggle the wrench around and down to get over the nut. I considered trying to reinforce the Saturn, as it does have some benefits (you can use it with the 2" water hose going to the oil cooler still connected. With BlythewoodJoe's wrench, I had to pull that hose off). I thought about putting a very small band around the wrench portion and welding it. Don't know if it would have worked.
REAT pics and story Clinto! Not so great that you had the leak in the first place, but all ended well. Watched your vid and she's purring right along. Nice job. Bummer about the Saturn head wrench. I've got one as well but have not used it yet. May need to fab something up before I do need to use it. Did you get any pics of Blyth's?
Thanks. Might as well return your Saturn wrench. Everyone I know who has bought one has broken it. Pic's of Joe's are on the link he posted above.