What color are your side view mirrors? Body color, or black ?
Most likely it is a DX. At least in Canada I know the DX's have black mirrors and the Si's have body colored mirrors. Most DX's do not have sunroofs, but I've heard of some that do -- probably added after the fact. I'm from Canada and we didn't even get the HF whatsoever, at any time... You're probably in the states though, sorry can't help more.