So not so fast regarding leaving I guess. I tried one more thing to address the rear differential gear noise. Kind of thought this was a pointless exercise, but I gave it a try. I had leftover sound dampening material, and basically wrapped the rear "differential" with it. Surprisingly it made a huge difference. All the way up to a steady cruise at 40 mph. I can kind of hear the gear noise but it is muted and doesn't have the annoying wavering intermittent "ring" to it. On or off throttle.
Although the temperature over 3 miles only got up to 110 degF (90 ambient) it is obviously not a long term solution to wrap it as no doubt the temperature would steadily increase. My plan now is to build a shroud around it with sound dampening material covering inside or outside or both, and then have a baffled inlet and outlet with a 12V fan to blow air through it.
Other conclusion is that the nasty gear noise is almost all from the rear, with the primary drive not making any significant noise as far as I can tell.
Cheers!
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