I installed a plastic hood for my forester https://www.subarupartspros.com/sku/m001ssa100.html but still paint did cracked because of the water. Have so much work to do to regain the shine again :(
I tried using white then switched to black. Using white you could obviously see the dirt but in my experience, it could be less noticed if it is black. Maybe you can wrap it with a DIY plastic just so the dirt won't stick?