For polishing brass name plates etc., I use three 0 or four 0 steel wool. You can polish to a bright shine very quickly. When happy w/ the result, use a red or black magic marker to re-fill the numbers or lettering, let dry, and then "lightly" polish again w/ the steel wool. You may have to repeat to get 100% . Testors "gloss coat' will seal the finish and color w/ a light spray.
As regards the gloss on our "COLLECTOR COLOR" paints, The pre-war colors were mfg. for a NOT " high gloss" look, and not "satin" either. I prefer to call it a 50-60 years old finish on a piece that was taken great care of. Several years ago, a Lionel standard gauge train collection was auctioned off at one of the major auction houses. It contained over 100 pieces that I had restored 42 years earlier. I attended the auction out of curiosity, as the collection was being advertised as mint original items. I had informed the auction house that 99% of the items had been restored by me. Nevertheless, the trains all sold at substancially higher prices then expected. My point being that w/ time, the nickel & brass trim etc. will attain the same kind of patina as an original. Just do a good job on your restorations, and paint.
I had commented earlier that I sprayed the inside of the body and roofs first, then the outside last. I just wanted to add that I never had a problem w/ over spray having to be removed first.
As far as primer goes, I am no expert, but only used primer when the roof or body had been repaired. this was to give extra adhesion to the repaired surface for the paint, and 100% even color thru out.
As for removing paint, I use a SEARS sand blaster unit w/ ceramic nozzle, and aluminum oxide for the media. I built my own sand blasting cabinet, and it will hold a state car body. My compressor provides 90# pressure , and my SEARS shop vac sucks out the dust so I can still see when the item is clean. Next I wash the body in the sink w/ liquid soap & water, & a 2" paint brush. Rinse off w/ hot water, blow dry, and do NOT handle w/o gloves. Right or wrong, this is how I did restorations. Last but not least, I use Art Warwick's dry transfer lettering available from J & A Hobbies. Harry 
