A small mod to you code will make it work on eastern time

   if ( $res->content =~ /NISTSendTime = new Date\(\s*\"(.*?)"\);/ ) 
      {
       print "NIST Date/Time: $1<br>\n";
       @words=split(" ",$1);
       print "GMT ".$words[3]."<br>";
       @time=split(":",$words[3]);
       $gmt=$words[3];
       $temp=$gmt-5;
       if ($temp < 0) {$temp=24-5};
       $local=$temp.":".$time[1].":".$time[2];
       print "LOCAL ".$local."<br>";
   }
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