To start off here are some plans of the early versions of GT5, the picture are of early studies of the layouts of the menu's, its weird that the tuning shop was going to be part of GT AUTO, but then later was removed to its own.
Special Events(the events look shuffled)
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That looks so fake... I mean, read the descriptions! "Challenge the Invincible Driver, THE STIG!!!" I mean, that looks like it's been written by a 5-year old TopGear fanboy! Plus, the GT Rally thing has a grammar error, an incomplete sentence is in brackets, in between two exclamation marks. I mean, REALLY? 
And the Nascar thing. NOT EVEN FRICKIN' INTERESTING! And it's obviously been written by a 5-year old Nascar fanboy... Nascar is all caps. And the Loeb rally challenge has an incorrect logo.
And the picture below that -- seriously? The map shows Suzuka, but it seems the cars are driving on Tsukuba.
However, I must say, everything else looks... legit