@shanr Looking good. Though it looks like you forgot to download the updated model from livrestream #2. Download that one and copy your parts to the updated file.
You can also look on YouTube for wheel modeling tutorials, there are good techniques that will help you make the wheel one solid mesh.
Also here on CG Cookie there’s this one from when Jonathan Williamson modeled the wheels of the post apocalyptic truck.
https://cgcookie.com/lesson/modeling-the-tires