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I would check first for a loose fan blade or cooling cage on the A/C. That is the most plausible cause of the noise. Check that first.
You obviously have no idea of how these are constructed. I have been at this many years and have repaired dozens of this model. You just need to take it into a dealer as this is over your ability to work on. Sorry it hasn't worked out for you, but it has for nearly 10,000 of my customers here over the last 7 years. Have a nice day............