I don't think you'll find it's the intention to publish purely lower section rankings. The current list of 150 may be extended in the future and, if so, would inevitably incorporate a high number of lower section bands. There are a few lower section bands included now including quite a number from the first section in the top 100.
There is a brief description of the workings on the 4barsrest site but the system has been extended somewhat since that was written.
Perhaps it's time someone asked for an updated version.