I am currently playing on a server (Kirara 5) and some of the players / devs are trying to prevent Pam's harvestcraft's salt from being unified to Gregtech's salt.
That way we could make pam's salt from running water, use it to make food but we'd be unable to use that pam's salt for making sodium and chlorine inside an electrolyzer for instance.
I've done some tests, trying to remove pam's salt from the ore dictionnary but it is still unified to GT's salt with this script :
Even though pam's salt is successfully removed from all the ore dictionnaries entries, it is still unified to GT's salt.
As far as I know, Gregtech grabs every oredict entry when the game is launched and adds them to it's own list.
I've done little to no mod coding, I only have a rough idea of how it works but it may help other players on the server. This idea is to make a high priority event which would register pam's salt from the ore:itemSalt and ore:dustSalt, I don't know if it would have to happen during pre init, init or post init (again, my knowledge is very limited at the moment), but I imagine that's how this would work.
Any help is greatly appreciated!