Do another video but do a slow sweep from maybe the exahust to intake mani and probably do the same on the bottom so we can try to get a better idea of where it's coming from. In your second video it kinda sounded like it was related to engine rpm? Or at least was more consistent out of idle...

+1 for BPR7ES, based on your profile.Give this a read: https://www.dsmtuners.com/threads/spark-plug-faq.233421/

I'll +1 the thermal. It's pricey but sounds deep and not raspy and should go on without any modification. Extreme psi has it the cheapest I've found so far.This is what it looked like on my 2g when it was running (my exhaust sits a little lower than it should)

Here's the links to the service manual downloads if you don't want to buy them. It's always easier to have a physical copy, though.1g http://www.dsmtuners.com/threads/download-the-1g-service-manuals.344490/2g http://www.dsmtuners.com/threads/download-a-2g-service-manual.324090/