I am looking at a Panasonic that has 3 speed options. 50, 80, and 110 CFM. I may just pull the ducting off of the fan in the laundry room right behind the closet that never ever ever gets turned on. I will, of course, seal off the outlet in that fan. I can "Y" into the duct as well if I have the motivation. It will be a while before I feel like getting in the attic anyway so I have time to think it over..... It should cool down enough by Halloween. 😂

I will get a thermometer in the rack and monitor temps at each speed setting and see which works the best with the lowest noise. Thanks for the input.