WAIT!

One of the sides of the logic board zig zag notches with large square teeth. Push the board back in slowly until you see the tabs line up with the 3 metal legs on the frame and the board can be flipped out like a page in a book! You need to see this at the bottom side of the Mac as you slide out the board. You do not have to slide it out all the way. Just pull back the board about an inch or a bit more for the tabs to line up to the frame...

What you are lining up with: