Smokey, You should be able to put the ground any distance away on the panel as long as the metal is clean. I always have chosen a good spot on the truck and used that ground point for the whole job. Seems to me there is another issue. If you still feel that the distance makes a difference why not get a small chunk of angle iron, clean it up, clamp your ground to it and then tack it to you panel as close as you want. If you tack it on one side you can break it off and move it as you progress.
