Chrome is a plating not a trim type. If you have a lightweight moulding with a clear coating on it it is aluminum. Stainless steel mouldings are not clear coated. The only chrome plating you will find on a car is a steel bumper, plastic, or pot metal such as a door handle
You can use just lye and water mixed up as a soak. Supposedly it's cheaper. Also, I've heard that easy off only removes the dye coloring but not the anodizing layer? So it can't truly be polished... it's what I heard i hope it can be polished cus I need to for my AR