Sigh as you like it. But when they don't even share basic suspension designs, I still say it is wrong to claim they are variations of the same chassis. Just becasue at some point they thought about using the LS chassis, doesn't mean the Mustang chassis is a variations of that design. Over the past 4 years stories have claimed all sort of things. In the end almost nothing is shared (chassis wise). If you don't even share suspension locating points, you aren't sharing much. Sharing the door handles is probably more significant than the chassis parts they do actually share. If you could point to one shared suspension compoennt (not including fasteners) I might feel differently.
Ed