[Richard Coutts-Smith]

Better described as a Wide "L" shaped plate...this also holds the guide roller behind the sheaves.
Fairleads = Roller Cable Thingy, or any roller guiding the winch cable.
The fairleads on the front, as shown in your pic, are nice and simple, they can be heavier and more complex than that: swing out rollers to pass the cable hook/eye through.
Just in case.... the wire rope is fed around the outer sheave and forward to the fairlead on the front bumper for when winching is required at the front of the truck.
Rich.