Both are annodized so you can't really shine them up. You must strip the annodization off to the bare aluminum to polish it. It's the annodization that's dull. Then of course you don't have the protective coating on them anymore. I chose to send to a polishing shop where they stripped and polished the pieces for me. You can have them powder coated with a clear when you're done or anodize them again. I chose to just leave them bare aluminum and will wax them. I stripped a junk piece of trim using greased lighting, did a quick polish, wiped with alcohol to clean (everclear is your friend!) then sprayed with a clear UV resistant (so it doesn't yellow) coating as a test, but the coating bubbled so I decided to just leave them polished and wax.
The grill is held on with about 10 nuts on the back side.
The window trim that's on the rubber gaskets is held in with a "j" type hook on the back pressed into a slit in the rubber. Since your gasket should be off for paint it should just pull right out. The trim that's on the door frame is "clipped" on. it's slightly bowed so it grabs the frame. Pry from the back side starting at an end and work your way around. Then again if it's at paint, you probably don't have the trim on the door frames.