Step 1: Materials Needed
You must read the image note.
Step 2: First 2 Steps
*No, I don't know the names of all the pieces, either.
Next, put the 7-stud white pieces on either side of the black pin, with the last hole of the white piece on the pin.
Install the second black pin on the sixth stud of both white pieces. See finished product for a visual aid.
Then put the gray axel through the end of the black V-piece. (The opposite side of the white pieces)
Step 3: Attaching the Mounts
Then, with 1 stud between the blue pin and the second set of mounts, add a gray 1.5 stud long pin with long side in, and attach the second set of mounts with studs facing out. Once again, use picture as a visual aid. Do the same for both sides.
Step 4: Adding the Mounting Pins
Step 5: Mounting the Grapple
The second picture is just to show the other side of the grapple :)