You could try this

my @info;
while(<DATA>) {
     chomp;
     s< ^ N \d+ \s+ >()x;
     if(m< ^ \* >x) {
          push @info => '!' . substr($_, 1);
     } else {
          push @info => m< [XYZ] ( [\d.-] +) >gx;
     }
}
print "@info\n";

__DATA__
N38 * TOOL 11: 0.125 DIA. FINISH ENDMILL
N39 M6T11
N40 E1
N41 S15000M3M7
N42 G17G90G0G8X-5.58Y-18.
N43 Z0.05H11
N44 G82G98X-5.58Y-18.Z-0.2R+0.01P50F100.
N45 X-3.171
N46 X-1.025
N47 X0.887
N48 X3.371Y-18.688
N49 Y-17.312
N50 X5.46Y-18.
[download]

Which appears to do the job.
HTH

_________
broquaint