Hello Mathew.
one option you might have is to use the surface wrap feature in the Edit in CAD Mode.
I would suggest you do wrap the individual components bit by bit.
Here is the example for the chassis the front and rear wing.
This is the result I got.
Now, I would delete all the surfaces inside the chassis and continue with the suspension etc.
The other option would be to go ahead and search for faults in your CAD model like described here:
Best regards
Sebastian