I can't seem to delete dangling dimension in the assembly model since I've upgraded to 2016.
I know I can hide them but how can I delete them?
Can you be more specific? Is this in an Assembly sketch, or a drawing view of an Assembly in a Drawing? And how are you trying to delete it. If you're in a sketch and getting the text box when you select it, that's the new Instant 2d feature. You should be able to select the dimension by clicking on a leader or extension line instead of directly on the value to delete it. Or turn Instant 2d off.
Dims will show up in the Display/Delete Relations
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