Yup, it seems that this mod needs data from all the meta files in the dlc.rpf:
carcols.meta
carvariations.meta
handling.meta
vehicles.meta (ofcourse 
ahha)
So it will be quite some settingup and ‘trail and error’ before you might get it to work
What i would recommend FIRST is to check if all these files are in your stream folder and then retry 
:
You can also find some of them in the original game folders if the mod doesn’t have them (find them using the OpenIV search method) and add those to your stream folder.
HOWEVER and this is IMPORTANT! : If you do no disable or either properly add the mod components (for the modshop) it might crash the game when people try to mod it! so be cautious with that.
I PERSONALLY heard that adding vehicle mods isn’t hard, but i have NO experiance in it so will NOT advice on it since i can’t guarantee it’s correct (i only use standard models or models without mods).