Injecting Vehicles\Weapons can be extremely easy if you know what you're doing. There are multiple things you have to inject for a vehicle to work.
These are just a few for example purposes... To get a full list. Open HHT v3, and go to the vehicle tag, and select a vehicle to see the dependencies:
- Collision Model
- Model
- Animation Trigger (Models Animation)
- Vehicle Meta
- Vehicles Weapon (If included)
Everything there is very easy to inject. Use HHT v3 for everything there but the model. Use pokecancer's Xinject for the model, or... you can inject it manually and save a little model space, but this is harder. Now Along with those things are dependencies that you also have to inject. For example... If you inject a model, you must inject a shader to go along with that model or else the game will not load and will freeze at the loading screen. So in a nutshell, when you inject something... Inject everything it needs too (dependencies).