If I recall correctly, one half of the timing cover is hard to replace, and the other is pretty easy, but I can't remember which is which... Helps a lot huh?
Maybe having some louvers pressed into the skid plate to help direct some air in there, while still providing impact protection would help. Even if radiant heat is the problem, the cool(er) air being forced in while the car's in motion would likely still drop the temps some. (?)