Just give them the 14 Words and 88 Precepts and let them react to them, digest them.
From this, have a discussion and above all, let them talk. Don't oppress them. Just ask mild questions that will nudge them towards your viewpoint. In fact, after being ensconced in NS/FA for so long, you might have forgotten a thing or two which are not totally without merit from what composes their entire worldview, although obviously most of it is utter trash.
Again, 14/88, don't waste your time.
There will be plenty of future opportunities to push these neo-converts towards more content.
Understand also that many of them have been literally physically afflicted, in that there is no point making them fill bad and weak just because they do not have an ubermensch /fit/ body or don't even have the genetics.
Tell them they can contribute to making sure this will never happen again, that their sufferings will not be those of our children.
But never derail from the goal of making them understand the Laws of Nature. One must protect life and make it beautiful.
Destroy the clown world, egalitarianism and globohomo.
Sanity in mind and body is something to strive for.
Ask them what makes them so furious about NS posters and propaganda too. Is it normal that they get salty and start seething at the view of noble, functional families?
Is it normal for girls to be look like trash and drown in vulgarity?
Also, many hate authority and the military.
This is fine, there are many free minds too. But they must understand that there are evil people out there who would not hesitate to destroy what you like: your life style, your environment (that's the ecology dash in the discourse), your culture and even your family.
Some also think Das Kapital is a manual guide towards utopia. A few concise arguments against it are necessary.
Attack (((Marx))), attack the writings, condemn the failures of communism as logical consequences of a model that is anti-natural and cannot work without an inhumane use of tyrannical power. Show how communism evolved in form and how it wrought destruction.
But again, read the full content of 14/88, especially the 88 Precepts as they were made to win arguments.
It is a key component of the future White religion's backbone.
Anyone here who has not read the full range of 14/88 material is a LARPer.