Original VTEC models will either have a "GS-R" badge (92-93,) a "DOHC VTEC" badge (94-01) or a "Type R" badge ( 97?-01). Mind you this only works if the original badge is still there, and some idiot didn't put the badge on their RS/LS/GS/SE.

The wheels are not a very good way to tell, as many years used GS-R wheels on other trims.