I need to create overall dims on a drawing of a complex form.  Most, if not all, of the outside edges are silhouette edges and SW won't allow me to dimension to them.  It suggests that I create a silhouette split line to dimension to.  I tried that, but the split line removes a porition of the geometry.

How can I create these dimensions?

I know it's a bit cryptic and a part file would help, but I can't send this customer data over, sorry. This isn't what I'm working on, but imagine trying to create overall dims of orthographic views of these headphones: