Select Code to Download

my @array1 = (
   [ id1, ... 169 other fields ... ],
...
   [ id5, ... 169 other fields ... ],
   ... ~50k other records ...
);

my %array2 = map { $_->[0] => $_ } @array2;

for my $array1_rec (@array1) {
   my $array2_rec = $array2{ $array1_rec->[0] }
...

   ... Change @$array1_rec based on values from @$array2_rec ...
}