Aligning assembly model to XYZ

I have an assembly model that has gotten rotated by some unknown angle around the Z axis.  How can I rotate it to make it align perfectly with coordinate axis?

I've tried rotating with the 'Rotate Component' command, but I don't what angle my component is wrt to the X axis.  And I can't figure out how to measure that angle either.

SolidworksAssemblies