Finding relation between Nominatim row and gb_postcode table row?

Currently I have PgAdmin 3 open with a copy of the Nominatim DB I processed on a Linux virtual machine. I imported the gb_postcode.sql database successfully from the Nominatim documentation but I'm struggling to find a way to match a row in my main placex table in Nominatim to my gb_postcode table that's been imported.

Both tables provide a Geometry row, of which I tried using ST_Intersection on but the result was beyond inaccurate (returned 1.6m records rather than a single one, or a small subset of data).

Is there any way currently that will allow me to find a relationship between a Geometry object in a Nominatim record (such as 0102000020E61000000500000014A5CEED6F5A01C07D6F78E68A1A4A4091E398767B5A01C08A517C21891A4A404221020EA15A01C02E05FFB6821A4A405698631E9E5A01C0CBC1C7BB7E1A4A40A53D14BB6C5A01C026A36F777B1A4A40) and the Geometry object in the gb_postcode table (such as 0101000020E61000005D96EA24715B01C0A76FB0828F1A4A40)?

For examples sake, these two Geometry values are matching for the same street in the UK, but I'm struggling to relate them programmatically.

Thanks in advance.