Numbskull, did you try the earlier hint - writing down a list of six, seven eight of the extra words? They have something in common, that should lead to the systematic extraction.
PS Do you need them in you have all the thematic stuff?
Thanks for the tips folks. I am finished!
Very, very nice, even if it took me far too many hours.
Luckily I have a day off tomorrow, so will save the IQ, and savour that then. I see a forum thread building up for it but haven’t looked yet.
Orson - I agree - after completion used my chambers crossword companion to look up more 'containers' - learnt a lot - like the old 'chestnut' (probably not true) ... how many words do the Inuit have for 'snow'...