As the Queen of Mississippi, a refitted ocean-going craft, pulls in for its maiden stop in Vicksburg at LeTourneau Landing this morning, the outline of a vehicle buried in the silt of the Mississippi River is recognizable in shallow water in the foreground. Warren County Sheriff Martin Pace said crews would attempt to pull the vehicle out today, but nothing was known yet about its contents or ownership. About 100 passengers were on the boat, which was to leave the city today for Memphis. The boat was forced to stop at LeTourneau, instead of City Front, because the river’s level was at .49 feet this morning, nearly 43 feet below flood stage and about 25 feet lower than the average level for this time of year.