See if this shows it better.
It isn't complicated, it just might look that way! I had to spread the mounting points out because a small mounting point on the thin sheet metal wall of the drum would let it be too flimsy, which is why there is so much steel for the hinge.
Also, I knew I had to back my pivot point out to allow it to lift and not catch that lip. Although, I went ahead and ground that lip up on the backside anyhow (which is why you can kind of see the gasket under that lip).