Congrats on your 98 Gsr. What color, leather or cloth , miles & most important have your timing belt, water pump etc been changed. If not do that first then your suspension, bolt ons, good tires/brakes. For exhaust I don't have one myself at present time but I'd go for the Apexi WS 2 or also look into a Thermal Research exhaust. Stainless steel throughout & no ricey sound & besides that's what I have on my EF hatch & love it. Had it 4 yrs.
Hope I could help, Post pictures