Been covering mine for 5 years now, cheaply. Truck warms up much quicker, I can tow all winter with it in there. I usually have it in there for 4 to 5 months. Pyro guage will tell you to remove it on the first warm day in the spring.
I have a piece of 1/8th inch polycarbonate cut to fit behind the grill, from local glass shop. On the Excursion it fits between the fiberglass frame & the grill. Remove the 4 screws on the top of the grill & set it in there. Same with the 05-07 Chrome Package grill.
On my 01 f350 I have to slide it behind the fiberglass frame in front of the radiator, I zip/ty it to the supports & the grill installs up to the poly flush.
Poly is usually around $25 per truck. It's not visibly noticeable, yet protects the cooling fins from winter grime.
Used Plexiglas the first time, & it worked until a high speed run shattered it. Polycarbonate is good for well over 100mph, (I've been told)
