i can't tell from those pictures. are the drop plates offset? do you have a pic of them not installed?
either way - i cant see how youd have an issue witht eh axle length.
scenerio #1: not offset - your axle (CV's) would need to be stretched the thickness of the metal (1/2")
scenerio #2: offset thickness of the metal (1/2") - your axle (CV's) would be exactly the same as stock length
scenerio #3: offset more than the thickness of the metal (1/2") - your axle (CV's) need to be compressed the offset amount.
There is quite a bit of room in CV's. think offroad guys with 13" travel in the rear trailing arms.
i cannot see a scenario that you are not fine.