I initially had a small grill block (Just the upper part of my grill. and originally on the back), and that was on all last summer. This winter, I blocked the lower part of my grill and then moved the upper to the outside as seen here:
The opening on the driver's side is for my tranny cooler. They are a little hard to see, but there are two slots in the bumper that feed air into the radiator as well.
No summer data yet, but I don't expect it to overheat.
Mike