The pilot of an amateur-built Long EZ/XP stated that while in cruise flight, the engine lost all power and he made an attempt to land in a field. He overshot the field and hit a power line. A cursory examination of the wreckage by a Federal Aviation Administration (FAA) inspector revealed that the fuel tanks were breached, and fuel spillage was noted in the surrounding vegetation. The FAA inspector planned to further examine the engine after wreckage recovery; however, the wreckage was recovered to an unsecured auto salvage facility and "worked on" by one of the airplane owners, without the FAA inspector's permission. A subsequent examination of the engine by the FAA inspector established compression and valve train continuity, and no mechanical anomalies were noted.