Thanks for the link, Ranger16! I'll hit Harborfreight this morning. I'll be curious what it shows.
Yes, I know the coolant needs time in the radiator, to actually cool. To be honest, after the radiator was boiled out, was somewhat disappointed, far as I'm concerned, should have been much cleaner. Especially with what the SOB charged me. But, when your between a rock, and a hard place...
Re-coring is usually only needed, for 'damaged' cores, right? Been to dang long, since I've messed with these things.
Overall, the radiator looks in good shape, including the cores. Unless it has a bunch blocked, from leaking. I'm going to hunt down other shops, in nearby towns, while I'm thinking things out.
Unless there's something else going on, there's no reason the radiator isn't enough. Except, not being done right.