Thanks for all of the replies and comments. I spoke with the dealership, and they promptly got the correct one to me, and I returned the tender with the lighter attachment.
As far as my desire to be inconspicuous, I don't think it will be a huge issue. I pull straight-in now (as opposed to backing in).
I have been leaving the hood slightly cracked, as that is what the instructions recommend. The seal is pretty tight when the hood is closed the whole way. Any thoughts on why the instructions recommend keeping the hood cracked? Heat?