Okay, sorry. You're looking online for something perfect, that someone else has experience putting on their Altima, and yet remains different from what has been posted online. Is that correct or is there a better way to articulate what you are looking for?
You know what might help, posting a photo of your unique ride setup from the side and rear. Then we can see your style and flow lines a bit and could envision a spoiler.
I am wondering my first question, do you like a lip type or a wing type spoiler? If wing type, can you please take a measurement between the trunk lid support beams? That would be useful for mounting point consideration. I think they are in there diagonal, so it may be difficult to describe the measurement. If you want a lip type, I think that can be stuck onto nearly anything.
There is a Made in America company called DAR Spoilers that does custom... not sure how 'custom' they get and if it's your thing. I like the ones with a center brake light... kind of. You could always paint it plaid or polka dot to be unique!
