Everything is working fine, just need to remove "Dependancy "/assetpacks" in the fxmanifest and change in all vehicles.meta the line
<audioNameHash />
to
<audioNameHash>police</audioNameHash>
Or any other vehicle sound name.
Interior is working fine, just open vehicles.meta then search for "vehicles_gamma_interior" and replace this :
<Item>
<parent>vehshare</parent>
<child>vehicles_gamma_interior</child>
</Item>
With this :
<Item>
<parent>vehshare</parent>
<child>vehicles_race_interior</child>
</Item>
<Item>
<parent>vehicles_race_interior</parent>
<child>vehicles_gamma_interior</child>
</Item>