With BRE or without?

Yes. Generally I dont like those spoilers, but since I've seen more and more pics of them, I like them now. The spoiler especially suits your car for a couple of design reasons too. 1 - black and yellow makes corners and creases look sharper, 2 - your yellow mudflaps point sharply downwards, the spoiler pointing upwards finishes off the lines of the car on the top as well as the bottom. Or maybe you just wanted a simple "YES" ????? well in that case.............. YES !

Thanks Alfadog, you explained it with a good feeling for the design and lines. Perhaps Mike makes this a poll 'cause the general question is "how much stock"

Sorry Rolf, but that's not a BRE spoiler. That's the first rear spoiler for the S30-series Z that was made in Japan, and has widely been mis-attributed to BRE. In fact, BRE had nothing to do with the design and development of that particular spoiler. Pete Brock himself has made this point in the past. I think they sold them and that's why many people think they were a BRE part. Maybe yours is a USA-made copy of the original shape?

That design was offered as an Option in the Japanese market from 1969, and was superceded by the plainer design without the ribs on the leading edge.

I say, if you haven't got holes in your tailgate then leave it off. If you already have holes then put it on.

HS-30-H, sorry to say you are incorrect, it is the BRE spoiler if you need more clarification see Road and Track Nov 1970, there is a VERY clear photo of the spoiler on the back of the #46 BRE Z and it is the Japaneese only spoiler that BRE used.