I knew that installing my car lift would be a boon for really seeing the truth under my 240.  For years, I've laid on concrete in the dark trying to get an accurate picture of its condition.   What I was surprised to see in the light of day was the rear control arm on the passenger side oriented so that the 'concave' or 'recesses' are facing down.  The drivers side rear control arm is oriented in the opposite fashion - facing up.  Is this 'Datsun design' or a mechanic's Friday afternoon special?

Passenger side (looking rearward):

 

Driver's side (looking rearward):

That is how it was built.

Yep, same arm, just flipped over.  I had the same questions when my car was restored.

Hihi.. yes it was very clever of Nissan/Datsun... one (size) fits all!!

Whew!  Shaving those costs down by producing the identical part for two purposes.  

Thanks!

It makes off the shelf parts storing a lot easier. Just go get one and you can't be wrong. This too confused me a few years ago. Pretty forward thinking I would say!