As the title says
Any suggestions?
It's generally recommended to you use a soft microfiber cloth lightly moistened with water. Do not use any alcoholic based solvents.
I use the microfiber cloth that was given with my Macbook, works quite fine.
I would recommend to use Hydrochloric Acid, but only for the outer casing. DO NOT put the HCl on the screen. For the screen I would recommend something just a tad bit stronger like Nitric Acid. These two will definitely do the trick for you.
and the screen was covered in blotches where it was no longer glossy anymore
How do you get smudges off the aluminum?