depends of the pre98s have a wide enough underpassage. look at the pic my brother posted. if the pre98 has a narrow straight passage, then the post 98 wont fit into the passage because its piping on the left goes further left than the pre98. u might run into the opposite problem of what my brother did.
I'd have to assume that it's the differing bends you're talking about - it WILL fit . I've NEVER heard of one NOT fitting . There is more than enough ample room under there . The only difference under there are the different shaped gas tanks , hence the different shaped bends .