Just pulled my front wheels and rear ones to put in new center caps that go better with my color scheme. The only holes I can find when looking at the wheel well are the foglight access doors which are rectangular and as you look at the wheel well on either side of where the suspension comes out, on the back wall at the bottom there is an open round hole on the left and an open oval hole on the right. Those are the only holes I could find and both are open on my car, no plugs.
Hope this helps - Pat