use these items:
(1) can of grey filler primer if there are scratches,
(1) can of silver spray ,
(1) can of clear cote,
(1)800 grit of sand papper
well in the picture its not noticeable .if you want to do propper job you should take 800 grit sand papper (waterproof). sook it in the soopy bucket of water like dish washer soop.use the sand papper gently until it goes little fade then clean it with water... remember where you paint there shouldnt be oily.then dry it and use the same matching colour of spray can.do 3 cote of silver spray each cote you should wait 5 minutes after that 3 cote of clear cote and the result will be like original new wheel cap.
well look at this my car had bad rust on the rear fender which i put the new piece and colour all rear fender and rear whole bumper.no body can tell that it was painted and trust me i did with the spray can and the person who mached the colour he was freeked out that how i did with the spray can lol .well for the shiny and and rubbing compunding i did deatling.
http://i267.photobucket.com/albums/ii318/RedMustang71/acuraa3back.jpg