You might want to look at the good old Curses module, which will give you complete control over the output. Here's a simple example:

#!/usr/bin/perl

use strict;
use warnings;
use Curses;

initscr;
addstr(10, 15, "mystuff");
refresh;
sleep 3;
addstr(10, 15, "OVERWRITE");
refresh;
sleep 3;
endwin;

__END__
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