Foamie Window and Door Rough Openings

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I'm building a Foamie with fiberglass/epoxy skin. I want that protective fiberglass coating wrapped around the opening to prevent water intrusion between the foamie layers if/when the window seal fails.
Did you cut your openings after applying the fiberglass?
If you cut them before, how much fiberglass thickness did you account for for the rough opening?
I know glass doesn't like hard corners, but with tape applied on the bias, a decorative trim ring around the windows to hide the broken strands, and maybe a small radius I think its doable to apply the glass into the opening after the shell is glassed...but what do I know. Just hoping to get some other opinions before moving on.
I'm building a Foamie with fiberglass/epoxy skin. I want that protective fiberglass coating wrapped around the opening to prevent water intrusion between the foamie layers if/when the window seal fails.
Did you cut your openings after applying the fiberglass?
If you cut them before, how much fiberglass thickness did you account for for the rough opening?
I know glass doesn't like hard corners, but with tape applied on the bias, a decorative trim ring around the windows to hide the broken strands, and maybe a small radius I think its doable to apply the glass into the opening after the shell is glassed...but what do I know. Just hoping to get some other opinions before moving on.