Rusting doors

I own a 96 chevy pick up Silverado Z71 extanded cab, both of my doors on the truck are rusting out, but only on the bottoms of the doors. Can anyone tell me the best way to fix the problem or do I have to replace both doors.
Thank you

I own a 96 chevy pick up Silverado Z71 extanded cab, both of my doors on the truck are rusting out, but only on the bottoms of the doors. Can anyone tell me the best way to fix the problem or do I have to replace both doors.
Thank you

the best way is to remove/replace the door skins and with rustproofing and sealing this would work very perfectly..

since this is a 96 perhaps scrap yard doors...or even less expensive fix would be fiberglass the skin .where the door rusted..