Not a motor home but I put black fiberglass screen between the grill and the radiator of my 96 F350, it worked very well and is fairly easy to change. I have not done it to my new truck but plan too.
Hope this helps
Jim & Debbie England
Do you have Gas? 2015 F350 6.2L CCLB DRW 4.30 axle. 2012 Yellowstone Ridgeline 34RLT Fifth Wheel