Modded kits and multiclass

Lunever

I would like to apply the kit Arcanist to an elven fighter/mage/thief, since the arcanist basically uses magic exactly as my favourite DnD paper&pen campaign of old had been for decades.
However, if I use EE-Keeper to set the kit Arcanist, it doesn't actually modify the spellcasting behaviour to that of an arcanist, it just contiues to use up prepared spells the Vancian way.
Is it possible to modify a multiclass mage into a functioning multiclss arcanist?

TwiceTested

I would make the arcanist, as a single-classed mage first. Then use EE keeper to change it to a fighter/mage/thief and set the levels for the class to 0/x/0 where x is your mage level (not sure if you are starting in BG1, which the level would be 1, or BG2, which the level would be 7, I think?) Then re-load the saved guy and you'll level up the other sides of your character and you're done!

DO NOT use the cheat code ctrl-r to heal your character. This will remove some permanent effects the kit uses to change the spell-casting appropriately and get everything to work correctly.

Good luck on the game, and I also love the arcanist! It's a BLAST to have sorcerer spellcasting while changing out your spells! You can also look up 5e spellcasting, which would change spellcasting for all classes that way. So your druid has this type of casting along with clerics and such. Edwin is SO BROKE with 5e spell-casting.

Lunever

@TwiceTested : Good idea That might work, however my current SC / current game is to far advanced already to make me want to restart or to risk installing additional mods after EETrilogy, however I gonna test your suggestion with the next character / next game.