You can get buffing wheels at just about any hardware store that will fit a Dremel or you could get a buff to put on a bench grinder/jeweler's lathe if you happen to have one of those.
Get either flannel or muslin and for a handheld rotary or a bench grinder buffing wheel, take out the outer ring of stitching on the wheel to make it softer. Take it outside and run it against a screwdriver tip to tear up the outside edges and pull out any loose threads/lint.
Of course be sure to follow all safety considerations - if you have long hair, pull it back into a bun, take off all jewelry and wear short-sleeved, close-fitting clothing and eye protection. Especially in the case of the bench grinder or jeweler's lathe, the amount of power to rip something out of your hand and send it flying is just incredible.
I like to soak the plates in Evaporust - it floats off a lot of gunk effortlessly. Then you just polish up the metal with a soft cloth and some metal or chrome polish. Even TR3 Resin Glaze will shine it up and protect it. There are buffing compounds to use with your buffs, but I've never gotten any of those. Between the Evaporust and Wright's or Brasso, it's always gotten the parts shiny and clean and that's where I have stopped. You can go a lot farther with it, though. :)