It will take a ton of material to mold that front and rear bumper into that kit. You don't want to use regular filler on it, not only because that would be way too thick, but also because it wouldn't have the flex that the bumper underneath will have, so it will likely crack or separate.The plastic repair material you would need (can't remember the 3m part number off the top of my head) is flexible, adheres better to plastic (you will still need an adhesion promoter), and is quite expensive. As wide as those quarter flares are, I would think you'd be doing well if you could finish the job with 6-7 tubes. Each tube costs about $55, you'll also need a special applicator gun that is ridiculously overpriced. You'll go through a ton of sandpaper in multiple grits as well. It's something that can be done, but it will be expensive as hell when all is said and done. Or you could do some ghetto job with bondo and/or expanding foam. Haha. Neither of those is right for the job, and they won't last in the long run.