The clamp sounds like a good idea, as long as you aren't using an original cam nut wrench, have the water pump off and both sides of the hood up. The nut has to swing 180 degrees to line up for the next face to put the wrench on. I am willing to give it a go and will see if I can get more swing from the drivers side. I still see, crank the engine till I can put the wrench on, set the clamp, turn the nut, take the clamp off, turn the engine till I can put the wrench on, put the clamp on, turn the nut, take the clamp off, turn the engine, put the clamp on, turn the nut.....No one said it was going to be easy!
Oh I forgot about having to walk from one side of the car to the other!