How to remove extra ground stations in existing save?

[sweatbox]

I have the option in the advanced menu disabled, however the extra ground stations are still there.

I've tried googling this subject and only found a single reddit thread telling me to set the "occlusion" settings in persistent.cfg to 1, which I did, but didn't help.

Is there anything I can do to remove these? Would I be able to make a new save somehow and keep all my crafts, missions, etc but have disabled ground stations?

[Gargamel]

Moved to Gameplay Questions. 

[jimmymcgoochie]

I've just tried this (admittedly on a brand new sandbox save, not an existing one) in stock KSP 1.12.3 and toggling the "enable extra groundstations" option in the difficulty settings and accepting that, then clicking apply in the settings menu, works every time both for turning them off and on. Click apply after turning them off and see what happens?