Hello Greg, I have a 778C linked to my Garmin 498 GPS. This allows me see my position, speed etc on my 778C. I can also mark waypoints. What I'd like to know, is when I pass over a brush pile, and hit the up/down, side to side key, a curser comes on the screen. I can then move the curser back over the center of the brush pile to mark it. I believe when I move the curser, it's actually changing the coordinates from where you traveled to after passing the pile, back to the point of the curser. Is that a fact? thanks!