Yes it will bolt right up.
NO
Will a 2000 chevy 2500 bumper fit a 2005 chevy 2500
You can sell a Silverado Bumper online from websites such as eBay auctions. Alternatively, you can also sell this item on local classifieds such as Craigslist.
Yes.
nope they are completely different
do i have to buy the brackets wit the bumper when i buy it
Unscrew it.
no
YES, As long as the 99 is not the new body design.
YES.
couple feet
Um... I would sure hope so since they are both 2003. But if you mean "will a bumper from a 03 silverado 1500 fit a 03 silverado 2500, (or the other way around)" I am not sure. It might, but the frame on the 2500 is bigger than that on a 1500.