Fetcher
Not sure how or why you removed the stake pockets, excessive heat could have caused the wave. I did not want to incure the cost of new side panels and had to weld in the entire lower 5 inches on both sides. I did not remove stake pockets but only cut out spot welds to free up the rusty 5 inch bottom of panel. When I spot welded the new angle strips on I did have to utilize some metal shrinking to resolve some small waves. do a search on this site and you will find a great deal of info on working metal including shrinking. Most of my problems were where the fenders bolted on and were there from the time I got the truck, my kids did not help as they would use the fenders as a step when exiting the box. Good luck.
