Hi Bill - The StreamPosition is the right approach to paginate through a large list of records. In the response of the first call you'll see a newStartPosition node. Take all the fields such as offset and latestCreateAt from newStartPosition and populate the startPosition values for the subsequent API calls to get the next set of records.
Sample XML Response:
<newStartPosition>
<latestCreatedAt>2013-07-31T21:33:59-05:00</latestCreatedAt>
<oldestCreatedAt xsi:nil="true" />
<activityCreatedAt xsi:nil="true" />
<offset>ID:1024814</offset>
</newStartPosition>