I'm not a retard, but I can't get the cover off to get to the heater core. There was evena screw recessed hidden in the front that took me awile to find . i don't see anything else. what am I doing wrong?

Look around for more hidden screws....especialy near the fire wall.
Also there is a lip on the cover that makes it difficult to remove the cover..it will break if you are rough with it.