I had to have my deck lid reglassed where the hinge bolts to the lid and the top center portion of the spoiler (It had a 12 inch crack that went through the spoiler.) I first took it to a body shop that works on Corvetts but they were very high on the repair cost. I then took it to a boat repair shop that specialized in fiberglass repair work, and they repaired it and for less and did a fantastic job. They cut out the cracked areas and reglassed the areas as needed. My deck lid has a small bow in it on the right rear. I left it alone . They also repaired my tail light housing it had small cracks in it.
You might try a boat shop like I did. There is a difference in the fiberglass that is used on our deck lids compared to boats. They had the glass on hand to make my repairs. It is now painted and looks great.