Well, to me it seems there is only one option for the skyline which doesn't have rails/fixation points.
The Thule 754 system:
http://www.thule.com.au/thule-rapid-system-754
From there, you need load bars and fitting kit and then the bike rail.
I'll keep you guys posted.
I've just re-ignited my interest for some and did another search on google for some.
Research has lead me to an old member with their GTR holding these:
I bought these off him I think and took ages to get my money back.
Said they were lost in the post.
Ah well, got my money back in the end and didn't deal with him again.
Few weeks later, he reposted same item for a higher price.