So your ex is a narc- according to YOU. You are not a psychologist. But lets pretend. So a court ordered psychologist establishes that dad has some personality disorder. SWEET. U'm no, see that alone ain't gonna grant you sole parental responsibility OR minimise the time dad has with the kids OR what ever you're trying to achieve.......
So that is my advice based on personal experience of the legal system.
The next part of my advice is based on my understanding of the law -
Here is a long version if you're interested in the nitty gritty of the law
The best interests principle | ALRC
This is a more concise explanation
Best Interests of the Child | Family and Divorce Lawyers
Pay attention to the "additional considerations" bit - Especially
"If the parents are able and willing to facilitate and encourage a proper relationship between the child and the other parent."
Recpectfuly, but none the less bluntly. So sure your ex is a narc or an f-wit or something else But there is nothing in the legislation that means that is a problem. Not unless, like I said earlier he has an established criminal history of child abuse / neglect.... But the legislation will look at your ability to facilitate and encourage a proper relationship... Now all punters can go off here is the information you provide. SO assuming he hasn't tried to see the kids into slavery in a Nike factory, or tried to sell them on ebay, or committed acts of violence that the courts have sentenced him for? then you're barking up the wrong tree.
Again, respectfully, but note the less bluntly feel free to ignore my advice - And I wish you well regardless of how you choose to approach this. But finding a solicitor that will prove to the magistrate that your ex is this that or Santa is not gonna help your case. What will help your case is proving that you're the best person for the job when it comes to primary care because there is no chance that you're gonna convince a court that dad should not spend time with his kids... U'm - If he has tried to sell the kids on ebay - then ignore everything above.