Auto body repair & detailing: attaching cab corners, pop rivets, hack job

Question
I have a 1994 S-10 extended cab pickup truck. It has a large hole plus rust along the bottom in back of the door on each side. I recently discovered that I could buy extended cab corners for the truck. How do I attach them to the truck and how might I rustproof the backside of these patches? I don't have a welder. Don

Answer
You could use pop rivets or screws but then what? How long do you want it to last? What do you want it to look like? You need to pull the box off to install the cab corners, that's a lot of work just for a temporary hack job. Take it to a body shop or buy a new truck, you would be wasting a lot of money and time if you don't do it right.
You could also take a vo-ed welding and/or body shop class, then you would have an idea as to what goes into this kind of work.
3M also makes a panel adhesive but you would still need to weld a couple spots.