In the domestic Japanese market, Nissan has had v8's since 1965. They were in the very large and luxurious Nissan President, the predecessor to the Q45, and which the first Q's were based on as well. IIRC, the first v8's were fuel injected 4.0l's with 195hp, not bad at all compared to other engines of the era. In it's day it was a very prestigious automobile, and sported almost every conceivable luxury feature at the time. It even had power vent windows! Along with seperate radios front and back, even seperate climate controls for front and rear passengers.
This site shows the 65-73 bodystyle:
http://www.geocities.com/MotorCity/Pit/3823/cedric.html
And here is the 74-90 bodystyle:
http://www.datsunworld.com/other/pres.htm
It's interesting that they kept the same bodystyle for so long, but apparently they do that quite a lot in Japan, If there is no real need to change it then they keep it alongside the newer models.
After 1990, it looks about the same as a Q45.