I noticed a small chip/nick on the paint on the flat part of the trunk underneith (i.e. where you can't see unless the trunk is open and you are looking at the thin bottom below the license plate). If it isn't noticible unless you are looking for it, must it be touched up or can it just be left alone?

If I do touch it up should I use the toothpick method or will a paint pen work just fine? Also, how do I get the paint color code for the vehicle (it's that smoke gray color).

Thanks!