Then all I can say is that the project was not scoped out in the beginning the correct way.
You only have to options the one you talk about or a new MY_Model.
You would only need to do a search and replace on 150 models using search for extend CI_Model
and replace with MY_Model.
Or your way try to hack the CI query which if you read up on it the database is not extendable.
What did you Try? What did you Get? What did you Expect?
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