It is a little bit of a bugger, mostly because it is a bit crowded back there. Work from the right side over the fender. Rotate the arm so that you can insert the cable through the screw hole. Make sure you push enough cable through so that when you release the arm it is still sticking through. Then move to the left hand side and, making sure the choke knob is pushed in, the choke plate fully open, tighten the screw. What makes it so awkward is that the barrel wants to keep moving towards the carburetor while you try and get all your fingers working together. And don't forget to hold your tongue right. Do you need me to take a picture for you?