This header section contains a bunch of left-justified
lines that are all shorter than 60 characters. Only the
headers and summary lines are interesting.

  Col1   Col2   Col3  Notes
  ----   ----   ----  -------------
     1    123    123  Foo bar baz
     2    741    200  Barbaz Foobar
     3    100      0  Boofar fazboo
         Total:  323

Next header section, etc.

##</code><code>##

my @extract;
while (<$INF>) {

    # Ignore useless lines
    next if length($_) > 60;
    next unless /^(\w|\s*Total:)/;

    push @extract, $_;
}

# Now you can process @extract for the interesting stuff
print @extract;