passing records from OAI-Harvester to MARC-Record

I'm trying something a little new for me and, as usual, the first time
is the hardest. I'm harvesting MARC records from a repository and want
to modify them. In the past I've used LWP to retrieve raw XML, parsed
it, and turned it into a MARC structure. Now I'm trying to do things the
"right" way. 

Once I've got a MARCXML record object, it seems to me there ought to be
a simple way to turn it into a string and grab it, something like this:

$results = $harvester->listAllRecords( metadataPrefix => 'marc21'
);
while ( my $data = $results->next() ) {
	my $header = $data->header();
	my $metadata = $data->metadata();
	my $marcxml = ... missing link is here ...
	my $record = MARC::Record->new_from_xml( $marcxml );
	... good stuff goes here ...
}

Or maybe there's a more direct way. Anyhow, I've looked around a bit and
haven't figured out a solution, so I would be greatly obliged if someone
could point me in the right direction.

TIA,
Mike
--
Michael Kreyche
Systems Librarian / Associate Professor
Libraries and Media Services 
Kent State University
330-672-1918