my @fieldnames = qw/cellsiteID sectID mcc mnc lac ci bscid bts  bearing mscID lat long tilt agl/;

my %hash;                          # you'll want a better name :-)
while (<OSS>) {
   @hash{@fieldnames} = split /,/;
   my %new = %hash;                # new values go here
 
   my $key = join "_", @hash{'cellsiteID','sectID'};
   next unless exists $h_ssect{$key};
   my @scoutSA = split(/,/,$h_ssect{$key});
   for my $f (@fields) {
      if ($hash{$f} ne $scoutSA[$ocfg{'oss2.primpos'}]) {
        $new{$f} = $hash{$f};
        push(@{$chged{$key}}, $hash{$f},$scoutSA[$ocfg{'oss2.primpos'}] ); 
   }
   # ...
}