I do not have a 98, or a FSM for one, but the 95 still has the speed sensor to ECM coming from cable driven speedo. I know the 2003 uses electronic sending unit at transmission, and thought the model switch in 2000 was probably when they changed. I have wedged an electronic speedo into my 93, so you can do creative things to make it work.
You would have to check the FSM, or find a 98 same model to compare. Or a member may chime in.