FA-37 Talon Stealth Fighter Jet

Hi Keo, these particular models are a little out of my depth and what I've discovered is they need to have the wholes on the mesh fixed up first before they can become a solid. Something I have yet to learn about in Sketchup. As this looks like that needs to happen first before being converted to.STL from SKP. I've posted my progress here so far with the hope someone with with the ability in Sketchup can take these files further to completion.
Please note these files were originally converted