what is NOS?
 

real new to this so still loaded with questions what is NOS? qand how do you determine if your cars sheet metal is original or not?

New Old Stock (or Nitrous Oxide)

Usually means parts found at various and sundry GM dealerships, Car dudes garages, etc. that is replacement sheetmetal and millions of other parts.

In my opinion, the best way to tell if it's GM sheet metal is the fit. The other tell is the condition of the fender/hood/part. Does it have a GM part number?

Of Course, I'm using GM as an example. Ford same, Chrysler, well, they are a fanatical bunch, I'll let one of them chime in.

Hope that helps.

the reason i ask this is because i have doors on my car that in the jam between the fender and door it has rubbed the paint off why is this and can it be fixed or do i have to buy new sheet metal?

Anything can be fixed and it may even be original and simply out of alignment. A good bodyman can tell you if it just needs some shims or if it truly needs sheetmetal. If it does need sheetmetal, the NOS is worth the money.