Identifying Rear Control Arms

I got a set of NOS Z31 rear control arms in a trade a couple years ago. They came with some other parts and I was told they are the later style (longer) control arms. Short of dropping my current ones and comparing them side-by-side for a small difference in length, are there any other ways to confirm whether these are the earlier or later style arms?

I seem to remember reading something about a difference in brake line clips between the years. Can anyone expand on that?

I would like to swap these in if they'll fit - but if they require different brake components, I'm planning on swapping in poly bushings to my current set instead.