Go to the 'Options Bar' and change the 'Subtract from shape area (-)' to 'Add to shape area (+) as I have encased in orange.
Those window areas will now be filled in with your foreground color, in my case black.
Next, with the 'Direct Selection Tool (A)' still active & still on 'backgroundwindows' layer, click on the outside path line as I have captured and hit the 'Delete' key on your keyboard. Now all we ahve are the windows, which is our goal here. Certainly saves a lot of time drawing them in again.
Now lets customize the windows with a a white tint. Do this simply by clicking on the 'Layer Thumbnail' as I have captured. And change the color to white (#ffffff) in the 'Color Picker' dialogue box. Then set that layers opacity level to about 23%.
Apply the same technique to the original 'Shape 2 copy' layer.
Duplicate, drag below the original, 'Direct Select Tool' and Shift + click to select the foreground windows, 'Options Bar' and switch to 'Add to shape area', then delete the outer path so that the foreground windows remain.
Click on that 'Layer Thumbnail' and change color to white, reduce opacity to about 43%.
All that remains now are fine details, amount is up to you. Below is my final image after adding detail to the hubs, lights, other highlights. Hope you enjoyed this tutorial.
A scenic version.
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