In 2007 was in Southern Utah spring time and the Honey Bees were very active.
Neighbor in CG was out cleaning and straightening radiator fins due to all the bees impacted & stuck on radiator. Took him over 2 hrs.
While he was doing that I went to a hardware store, bought some 1/4" wire screen, folded it in half off set so that openings were 1/8" then attached it to inside cowling of hood/grill opening with zip ties. When you open hood it moves with hood so it is completely out of the way.
I used the 1/4" wire screen cause I was worried that 'window screen' would be too small/tight woven and block air flow (like the cold weather kits we used on old oil rig trucks during WY winter).
Have to replace zip ties every once in a while but screen is still in place and other than just a quick hosing when washing truck I have NOT had to clean/straighten radiator fins since.