The fuselages are very different in their approach externally
firstly the older kit, being of a later variant, has some nose strakes to be added, though the slots need cut out first
then the strakes can be added
as you can see from the internal comparison the older model also has an option of external detail to be added
firstly on top
then, after opening various holes in the side
further intakes. none of these additions on the later kit, which is where I would have expected them, presumably because they did not exist on the earlier variant.