Not sure why the original chrome one corroded, but Austin and I thought maybe the PO hung the gas cover over it to avoid getting it on the paint, which is what I've been doing until Austin pointed out that the inside has a little hook for that!
^^^also, decided to go with the polished silver versus the chrome to avoid this again and since the wheels are silver (salt in Maine isn't forgiving for chrome), it matches just fine and not out of place. But boy, that corrosion bothered me tons, while the rest of the truck was literally show room condition.
Also, the chrome was more than twice the cost of polished silver....can't see myself spending $150-200 on a gas cover; even as nice as the truck is.
They're all made from 6061-T6 aircraft aluminum, and the finish is whatever you ordered, like chrome or polished silver....they also have black and brushed.
^^^Instructions were telling me to take the faceplate off, which seems much more difficult (clips hidden underneath the plastic inside), than just taking off the cover and putting the new cover on the existing face plate which is what I did....2 minutes.