The '98's are still mechanical
A new TKO 500 or TKO 600 have both versions avail. for electric/mech. They also come with their own billet shifter so you don't have to buy a new Pro.5.0 type shifter afterwards to fit it. (I think the shifter they used was sourced by Hurst -I asked them once but can't remember the company they stated. It wasn't Pro5.0 though).
i just bought a t56 out of a 03. almost direct bolt on, only difference is the driveshaft. if it has a electric speedo you can use the speedcal extended range to correct it.
here's whats needed to convert from a t45 to a t56. http://www.corral.net/forums/showthread.php?t=372613