Carmen,
They aren't difficult at all to install. Generally there are two different types.
One has clamps that mount to the rain gutter, put it in place, tighten a couple of screws on each side, and you're done.
The second is a little bit more difficult, as you have to drill holes in the inside of the door frame and attach the visor with a couple of small screws on each side.
I opted for the clamp type, as I didn't want to put any holes in the truck. Since my truck is a 52, I have the split windshield that you don't. With that, I had to loosen up the screws on the interior side of the center post, place the center clamp in place, and retighten the screws.
Tuts59: I didn't really see any difference in the fuel mileage when I added the visor. It was poor before, and it's poor now. I can tell you, in wet/snowy weather, they do seem to keep the windshield cleaner than without.
As for cleaning, again I believe that depends upon what type you get. The one I'm using on my truck is a Pekat Skyshield and all of it is brushed/polished stainless steel so very little maintenance.
Blind spots: The only blind spot I experience is when I'm first in line at a traffic light. I plan on eventually purchasing a traffic light viewer, but even without it's not a big deal. If I recall correctly, the visors designed for your truck are quite a bit narrower than the AD trucks. As such, you might not even have this same issue.
