The easiest way to position the boat over structure is to use a wreck anchor and drop it directly into the wreck or reef. However, if the structure is small or in deep water, hooking directly into the reef will actually put the boat off the structure. Instead, approach the GPS numbers, find the reef on the depthsounder and determine the direction of drift. Then, motor upwind and/or upcurrent of the reef, throw out a standard anchor, and settle back over the spot. To fish different parts of the structure, let out more line, pull it in, or tie off to different cleats. Also, fish from different parts of the boat. A few feet forward or aft can make all the difference. If a spot fails to produce in 30 minutes, it's time to move.