I tried something different for closing the grill openings. The cure all Duct Tape! Half width fits between the grill members and black is hardly noticeable. I have been driving this way for several days and am amazed that the duct tape strips are staying put! I have seen my mpg go up, but since it has also warmed some here I cannot say exactly how much. I left the top slot open but covered the rest including the lower all black grill. Checking the water temperature it still is below 1/2 on the gauge often, so maybe I can do more, but am being cautious.
