This may just have been missed but I didn't see cam bearings on your list.All great points, thank you all. I'm climbing back into more diagnosing this weekend. I've been driving it daily with lots of seafoam in the tank, and 8 ounces in the oil. How far can I push the seafoam / oil ratio for a short period to make sure the insides are clean? I'll then drain, new oil, filter, new oil cooler lines, connectors, seals etc. Then start finding that noise. No noise at cold startup, loudest is 2 minutes after cold start, that's what you hear on the recording, noise drops continuously until full engine temp and it's just a single tap, tap, tap and almost can't hear it at idle. Engine and new trans run great, I would love to nail this down so I'll stay on it.
Thanks for all the comments and tips, I'll follow up as soon as I can.