Trouble thickening

I have already had some help with my design, but am still running into issues. I want to thicken my design by 0.5" outward but i run into rebuild issues. Is this an issue with the radii of the design being too small and is there a way around this? Also when i thicken the design the front 2 wheel fairings become solid instead of hollow as they should be. Is there any easy way to solve this? Any help would be greatly appreciated!

SolidworksParts And Features