It's really easy to do. I had to do this to a rudder on one of my airplanes last season. After leaving it out in the hot sun all day for the annual airshow I noticed it was a little warped when I went to put it away. I pulled out the heat gun and two minutes later it was good as new and no worse for wear. Like opjose mentioned, it won't work if you don't hold the piece straight until the covering is completely cooled.