This has nothing to do with planishing but I had to do some really serious patching in a section of one of my running boards. I didn't have a lot of issues with distortion because they are made of somewhat heavy material. they turned out really well but had some slight imperfections, to hide these and create some durability I sprayed them with a good bedliner material. I also did this because I didn't want to deal with scratching black paint during use. This is one of the few things on my 41 that is not stock but it looks great!
