My car came with front and rear hood from GT racing in glasfibre.
Now i'm trying to adjust the front hood but it seems impossible to get it to seal against the hood seal, the sides are way of even touching the seal... Is the fit really that bad?

sometimes yes.

remove the hook lock and front seal, see if it the hood is shaped properly for your car.
Then go from there..

springs on the front hinges will make the fiberglass bow up, so remove those as well.

Rich

I removed the lock catch and seals, dont have any springs on the hinges, with this done the hood fits much better, seems to be the bulkhead seal that makes the front half of the hood not want to seal properly.