Want to trade 2013 civic for SI?

So last year i got a 2013 Honda civic ex. We bought the car brand new and we're paying the car off monthly for 5 years. Just recently i have been wanting the SI version. The civic ex is an amazing car but i'm just having a hard time having fun while i'm driving. I'm thinking about trading my car in for the SI but i wanted to know first what i might be getting into. I was wondering if anybody has any experience with trading in their cars for something else (or even a trade similar to mine) and telling me how much more they had to pay (car payments, insurance, etc) if at all. I'm going to the Honda dealer soon to get some estimates but i wanna know from other people who have done the same thing what they had to do (don't wanna get ripped off lol). My car is still practically brand new. I was hoping to just pay the difference for the si with around the same amount of mileage (or even more, wouldnt really care) and continue paying my current car payments but i know it doesn't work like that lol. I don't even want to trade it in for the new 2014, i want the same year 2013 just i want the SI lol. Any help or feedback would be greatly appreciated!

I haven't done that but really look into the 2014 SI the style is much better and is faster too and you will have more fun