To quote Tom Hanks in A League of Their Own:

"Of course it's hard. If it wasn't hard everybody would do it. The HARD is what makes it great."

I know it's tough and not entirely on you, but stick with it and it will happen. It's near the end of a quest chain that leads to the second or third best weapon in the game. It needs to be hard, and boy is it satisfying when you down it.