^Those kinds of questions are pretty easy to decifer in your own head if you've already attempted some sort of aggressive fitment. Right now you're running 18x9 +24. Say you add half an inch to the inner barrel and half an inch to the outer lip.... you've got 18x10 +24. That should give you a...
If I'm not mistaken its pretty dang rare to find an EX that's 5 speed and also leather... Nice pickup. Make sure the maintenance is up to date. Welcome to the site
Smaller barrels will lower the offset. In your case, a half inch smaller barrel will leave you with 15x9.5 -26 ish. If you were to get smaller lips instead it would raise the offset and leave you around 15x9.5 -13 ish.
Not really sure how that happened unless you are super low... Any who, the lx and ex side skirts are the same. The only difference in 4 door side skirts is the years they were made. 98-00 and 01-02.