Drill two 1/8 inch holes on each side of the robot body, two holes for the arms and two holes for the ears. Your drill bit will wander a lot on the smooth, curved surface of the fuel filter, so first make a tiny notch in the metal using a Dremel cut off wheel or grinder. Start the drill bit in the notch and it will stay put.
The arms are made of springs with a terminal in one end. Use epoxy or hot glue to secure the terminal hand in the spring arm. These springs had bent ends. Snip off one bent end and use the other to screw the spring to the body using #8 1/2 inch sheet metal screws.
The ears are crimp sleeves held against the body with a #8 3/4 inch sheet metal screw.