I did mark the mask position in M8, that's how I set up the mask. Even so, I couldn't get the mask layer perfect because I could not adjust each part individually. Trying to combine 3 masks into a single layer cuts down the amount of adjustment you can do quite drastically.
I can't believe no one else runs into this problem.
A simiple solution it seems would be a module that let you apply any shaped mask to a layer as an effect. This would allow you to mask your outputs without having to dedicate a layer for the mask...
Anyone able to script something like this?