My carpet? it's factory. I took it out and sold it when I changed it to red last year then purchased new factory carpet from my cali homie for $50.00 shipped. Super hook up. And with that said it fits factory, since it's made for my RHD ITR.
Now if you want aftermarket like my red. I recommend Stockinteriors.com they are fast & fitment is proper. You just have to trim it at the door cills and cut the holes out for the shifter, ect. I got mine with the mass backing. It fit tight, but I think without it, it'd fit even better.