I have a Fiero GT spoiler I always planned on putting on mine. It is similar to the flat base one, but larger and a little more aggressive, similar-ish to the second picture you posted.
I actually, at the moment, have no idea where the spoiler is in my house
It MIGHT be in the shed, but I can't back that up
For reference;
On a firebird;
The pillars are in difference places than a firebird though, so they would have to be moved.