When trying to create a datum surface with this subassembly, the surface is drawn incorrectly when the assembly is inserted on both on the left and right sides. I would suspect the problem occurs due to the vertical faces and the lack of a datum surface on the overlay portion of the subassembly, just like in 2006. Why wasn't this fixed for 2007? Again I'm stuck with creating my own subassembly from the generic structures (which at least has improved significantly over 2006). It would be nice to use a stock assembly for widening that actually works.