my $MODFILE;
my @files = <Test*_Copy>;
foreach $MODFILE (@files) {
	# Need to Search and Replace Here
	#How to Search entire contents of file and Replace???
	s/Marry Had A\nLittle Lamb\nShe Was GOOD\n/CHANGED!!!\n/smg;
}

File Contents (Test1_Copy)
Marry Had A
Little Lamb
She Was GOOD
Not Changing this
Or This
Marry Had A
Little Lamb
She Was GOOD
Line 9
Line 10