Welcome, that's alot of miles you got there!
One thing, though. I heard your video and I hear what sounds like compression leaking (not surprising given your mileage). I heard that same idle whistle right before my spark plug popped out ( I was rushing one day and didn't tighten the plug down, I guess, I'm still not sure how that happened, but I digress).
Now, i'm not there, so it could be anything, pulley bearing, belts, but that sound is familiar to me. Here's a description of what may be going on with your plugs, BTW
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