"I realy want to change that weapons model, but there are so many mods for it I can't be bothered to change."

And you don't need to, simply pick the required ones and add them to your mod. (or if you just want to have them invisible for no reason, that works too I guess)

Includes invisible versions of all first person mods from the AK/car modpack, butcher mod pack and gage courier mods, except for sights and gadgets.