When I approach a waypoint I kill the big motor at 30' and go in on the tm, continually watching the depth finder. At 20' I slow just a bit and watch the (with depth finder) bottom. The instant I see the brush top I toss a marker to the starboard side.

Still using the tm, I circle and come at the marker at a right angle from my initial approach. It lets me do two things: I can size up the area for more brush and can adjust my visual of where the top may be, using the marker as a reference.

I might be coming in and see that the main part of the pile is 4' south of the marker, in the 6 o'clock position. This way I am confident that I am fishing the best part of the top and might even have seen a fish or two on the cover.

Remember that most gps units work best at a speed of 4-6 mph and their accuracy is (at best) 12-20 feet. That's not too bad if you imagine your boat in the middle of a 20 circle.

Hope this helps.

aj