What did you find difficult? Integrating Volumes?
I'm fine with Integrating Volumes. I'm fine with stuff that can be solved with "algebra". It was quite a while ago when I took Multivariable Calculus but I remember that I didn't like the last chapter in Stewart's textbook (whatever it was, I don't remember). I hate the stuff when you have to imagine that there are infinite number of vectors in 3 dimensional space.