That might not work on all your variable names or if some are formatted a bit differently ...

In particular, note that it's possible to go a little nuts with whitespace and the Perl compiler still calmly accepts it. That, and the same basic extinct syntax also works with arrays and array references, which KANAKADANDI has never said are not present in the code.

c:\@Work\Perl>perl -wMstrict -le
"print qq{perl version $]};
 ;;
 my @ra = qw(a b c d);
 my $ar = \@ra;
 print ${       ra   }[2];
 print ${     @ ra   }[2];
 print ${     $ ar   }[2];
 print ${ @    $ar   }[2];
 print ${ @ { $ ar } }[2];
 ;;
 my %h  = qw(a aye  b bee  c see);
 my $hr = \%h;
 print ${       h    }{b};
 print ${     % h    }{b};
 print ${     $ hr   }{b};
 print ${ %    $hr   }{b};
 print ${ % { $ hr } }{b};
"
perl version 5.008009
c
c
c
c
c
bee
bee
bee
bee
bee
[download]

Another point I would make is that a search for these extinct forms should be based on a rigorous definition of a Perl identifier (insofar as one can be defined in user code):
    my $identifier = qr{ \b [[:alpha:]_] \w* \b }xms;
(or that's my first cut, anyway — but it doesn't cover "fully qualified" identifiers). See Variable names in perldata.

I think the best automated search-and-replace is still going to need a final manual patching pass running with strictures enabled, which I sure hope KANAKADANDI is able to do!