Not sure about 1st gen but I really could care less.
2nd Gen: 90-93
3rd Gen: 94-01
Only major thing I can think of in body style is that the 94-97's have a 2-piece grill and the 98-01 Tegs have a 1-piece. Get a 3rd gen if you can. Spending the little bit extra for a 94 over a 93, IMO, is a great choice.