I'm stepping back up onto the old hamster wheel again......
What everybody usually calls the "BRE" rear spoiler, and what others ( as seen in this thread.... ) call the "432" rear spoiler - that's the one usually identified by the vertical ribs on its front face - would be more accurately described as the '432R' rear spoiler. This item was first seen at the press preview event held at Nissan's Ginza, Tokyo showroom on October 18th 1969, and was mounted on the PS30-SB model 'Fairlady-Z 432R' that was on display there. This model was a purpose-built homologation special, constructed and made available to the general public in very small numbers in order to legalise the model for Japanese GT racing. Nissan only needed to make 25 cars in order to qualify for the JAF GT class - so that's what they did. This rear spoiler also made it into the JAF homologation papers for the 'Fairlady-Z 432' ( NB - this is NOT the '432R' ) and 'Fairlady Z/Z-L', and also the JAF / FIA 3023 papers for the Export model 240Zs.
This "PZR" rear spoiler was also included in the standard showroom model options lists for the other current Japanese domestic models of that period ( November 1969 through October 1971 ). It could be optioned at time of order, and was sometimes fitted by the dealer supplying the car to the customer. We could call it a standard Japanese extra-cost option for all models, but in Japan it is more commonly known as the '432R' rear spoiler, because that is the model that it is identified as having originated from.
To sum up, this spoiler was standard equipment on the PS30-SB model 'Fairlady-Z 432-R', but was offered as an extra cost showroom catalogue option for the other models.
You're a couple of years out, Carl.
In October 1971 - with the introduction of the L24-engined models to the Japanese market lineup - the new 'smooth' rear spoiler ( without the distinctive vertical ribs of the 'PZR' spoiler ) was offered as an option across all Japanese market models. As far as I am aware, the ribs were deleted from the new design as they held water between them when it rained, and this water would flood across the window and into the gap between the tailgate and roof panel when the tailgate was raised.........
You seem to have managed to make it sound as though Nissan 'copied' the BRE design for the 'smooth' spoiler. I'd say the opposite is far more likely.
There is an illustration and instructions / dimensions for mounting of the later 'smooth' spoiler in the October 1971 factory service manual for the HS30, PS30 and S30 models. These are the exact same dimensions as the six mounting studs on the OEM early 'PZR' type ribbed rear spoiler that I sourced from Japan for my 432R replica project, and they correspond with the mounting holes for the standard smooth rear spoiler seen on all the UK export market cars.
Photos: 1969 Japanese market options list, 1971 Japanese market options list close-up, and October 1971 Japanese market FSM page scan: