Failed at the first step of de-snorkeling. some help please

[Bmod986]

Thanks for the help but i still cant push the blinds back. I even hit it with a hammer a few times. Softly but still it didn't budge. I know i have to start from the bottom but it just wont move and I dont't know how much stress that hing can take before it breaks. Im still going to try it but I just want to make sure its done right and i dont have to end up buying a new vent piece.