will 9" rims fit

[cre]

H&R racing springs only drop a bit over an inch and a half... unless they're old, sagging or you have a massive rear end. 1.6" front and 1.3 rear is what they say and the last person I knew who had a set measured about 1.75" in the front after 2 years on them. You on different size tires or non-OEM dampers? Different perch height or tire profile would account for the offset you're seeing.

Anyway, whether they'll fit or not is going to depend more on the offset than the tire size. 255's will fit comfortably on a mildly lowered MKIII and I suspect they'll fit fine on a slammed MKIII but may require rolling the fenders. Look in the tire fitment thread in the MKIII FAQ section, someone may have posted more first hand info.

So, I take it it's on either cut springs or coil overs... Have any pics? I've only ever seen one completely slammed MKIII (I think around a 4" drop) but his front weels were turned when he hit a small speed bump and it sucked the driver's side fender into the wheel well and pushed the passenger side out.... not a good example.