1974 Plymouth scamp Rear tail panel polishing

I was wondering how would you go about polishing or at least shining something that doesn't look like aluminum? I have a '74 rear tail panel plate (rear finish panel, rear backplate, ect...) that i want to clean it up and give it a nice shine nothing too crazy.

should i be looking for a chrome polisher? wax? Compound? Blue magic?
what type of material is the tail panel plate made of? Plastic? Potmetal?


.