Stock springs and stock ride height problem

Bilazaurus

Hiya. About a year ago I bought '13 370Z. It had Eibach lowering springs. I really didn't like the look so I wanted to swap to stock ones. I bought used sets, front and rear separately. Right from the start, pardon the pun, it didn't sit right with me. Rear was very high. But I wasn't sure if it's supposed to be like that. It drove me nuts. Then all of a sudden I had a thought and asked the guy who sent me those rear springs - do they come from G37? And they did.

Now, please, I'd like to confirm this. 370Z has different springs than G37? And going further with the question - G37 springs are higher and stiffer than those from Z's?

And if so, how can I recognize the RIGHT rear springs? I've seen some offers with unused springs but I just wanted to make sure (don't want to spend a fortune purchasing from the dealer). They have dots, right? Thanks in advance.