I worked on polishing the fan housing after returning from Spray Tech this afternoon. I started with maroon scotchbrite, then grey scotchbrite, then white scotchbrite. I rinsed off and dried the fan housing, then I made multiple passes rubbing in metal polishing cream followed by dry towel buffing and I finally got the result I was looking for:
Next step is to repeat the above process with the fan.
Thank you Jeff for the glass bead blasting suggestion. I wouldn't have gotten this result without it.