Yes, I think I can make the assumption that there will only be a single part to remove.  So that should do what I'm looking for.  I hadn't considered using the Where clause like that but it seems quite obvious in hindsight.

I only want to remove the numeric part if a SAON part has been removed, though, or else I risk removing road numbers.  (Ie "Flat 12 Blodwin House" should become "Blodwin House" but I wouldn't want "22 Acacia Avenue" to become "Acacia Avenue").  I should be able to handle that by checking the row count before doing that step though.

I'm going to have a play with it to test it but it looks like exactly what I'm after.  Thanks. 🙂