Apologies for cross posting but got no takers elsewhere in the forum.
Using drupal 7 I have implemented hook_node_access but am having real troulbe figuring out how to go a step further and achieve the following using hook_node_access_records and hook_node_grants:
For a given content type ('submission') I want to limit users with a particular role ('curator') to see only node that have a specific value set ('location')
An abridged version of my hook_node_access function is outlined below.
Any help greatly appreciated.