I used the same set up ( home made ,but worked )on a 2012 chev 2500 diesel and noticed that I had to cut part of the right flap as the exhaust pipe points right at the flap and was melting it....just an fyi.
I just use the factory mud flaps on my tug, but my very particular Father-in-Law had a much more effective setup. In addition to his standard flaps he had one of these brush-type guards on the back of the truck. It knocked down virtually everything that got past the flaps.