I have been looking at some pics of 240zs (as you do) and realised there are 2 types. A all horizontal one(2) and a horizontal with small vertical bits(1). I have included a pic. Why is this. Im thinking the year released.

They're the same bar, 1 has 'bumperetts' fitted and # 2 has removed them ( mag the pic & see the holes)

I've removed them on my cars as it only takes a love tap on the bumper to send them straight up into the bonnet

Steve