Great mod and it works legit. But there is one issue and it's not the creator fault unless he can somehow fix it but doesn't need to. Whatever loose items you will be storing in your car like beer case, ratchet kit or whatever, IT WILL fly through the car and then you have to go and pick it up.
I do have a fix for the items flying out. If you use the inventory mod and set it to maximum capacity (50 items) you can probably carry everything and it won't fly out.