Originally Posted by Nobody609
scotch brite pad and some elbow grease. if the previous owner used plastic paint, you have to fight through the "bond".
I'd use some lighter fluid in addition to the scotch brite pad and elbow grease. If the lighter fluid does not work, try a little
bit of acetone. Start on the inside with the acetone because it could damage the mask. It would be prudent to remove the lens during the entire process.