foreach (@old_records)
{
   my $name = substr($_,  0, 8); $name =~ s/\s+$//;
   my $desc = substr($_,  8, 8); $desc =~ s/\s+$//;
   my $date = substr($_, 16, 8); $date =~ s/\s+$//;

   $name = ...reformat name...;
   $desc = ...reformat desc...;
   $date = ...reformat date...;

   push(@new_records, 
      sprintf("%-7s %-13s %s\n", $name, $desc, $date)
   );
}