as for the wheels, you will have to basically start from scratch. you will need to start with rough paper and work your way up to super fine. Someone on the forum will have a better idea of what grits to use.
wet sanding (as Crone said) is using sand paper on your surface, but dipping it in water first. This will provide a natural, easy to clean, lubricant. Water is a penetrating fluid (grand canyon and niagra falls are good examples) so it will lubricate all the way into the surface of wahtever it is you are sanding. (think on the molecular level.) it litterally lifts the paper off the surface of your "canvas" as to protect against heavy pressure and uneven pressure. Its kinda like useing pencils under the palm of your hand as you slide it across a table top...
Also, water at the molecular level acts as a abbrasive (sp?) This is the leading problem with nano-technology. but anyways... lol. this helps remove molecular impurities and helps pull them away from your "canvas." In the case of body work, it is the paint that is being removed.
Depending on what you are wet sanding, and your goals... you should use a different paper grit, different amount of pressure, and a certain shape of "sanding block"
for body work, you tend to use a flat sanding block. to go to the metal, use heavy grit to get through the clear coat, then switch to a medium grit to get through the paint. once you hit paint, rinse your paper more often. the minute you think you are about to hit metal, or you see metal, switch to a finer grit. fianlly, once metal is showing, use a super fine grit to almost "polish the surface."
Once you hit metal, wash it with water. then use a harsh cleanser on it. Paint thinner, lighter fluid, gasoilne, turpintine(sp?) anything like that. drench it down. check for impurities.
let it air dry. do not use compressed air. keep it in a dust-free place (paint booth.)
apply primer.
wet sand if needed (probably use super fine grit)
apply paint.
wet sand if needed (probably use super fine grit)
appy clear.
if done properly, i doubt you will need to wet sand again, but you may.
as for the wheels, you can buy oddly shaped sand bricks to help with the oddly shaped surface you are working with.... of, my friend just turns his flat one around and uses the curved side for wheels and hard-to-reach areas.
