Severe damage on a SS spoiler, fiberglass expects come on in...

[Black94z28]

Was given this spoiler for my car. It is a true GM SS spoiler is the only reason Im going to attempt to save it.
I worked at a bodyshop for awhile so I feel pretty confident in repairing the panel. Only two spots Im a little uncomfortable with. 1. The corner piece thats busted and 2. the seperated top panel from the bottom. Any advice on the best approach to this?
Here are some pictures...
I wonder what happened to cause the damage??

This is going to be the hardest part to fix, the corner is busted and pretty much just hanging on by a hair...

Another view of the damaged end...Also you can see where the top panel has seperated from the bottom...

Another look at the panel seperation...if this wasnt a GM spoiler, it would be in the trash...

Although just look like spider web cracks, these are deep and you can feel them with your fingernails, probably have to take this down quite abit with 40 grit...

The spoiler on the car...BTW, I need a brake light if anyone has an extra?

Lines up pretty good however (cant tell though since this is just sitting on the car not bolted down)