I also have a 98'. You are correct on the bolt pattern. From what I read you can put up to a 12.50 tire on the 8" wheel. I plan on running 33-12.50-15 on my TJ with an eight inch wheel. Hope this helps.
10' JKU Mango Tango, TF perf. leveling kit, Rubicon shocks, 315/70/17 GY DT's, V-Tec Raptor wheels 17x9, fender trim, Warn M8000, SB front bumper, aftermarket HU and powered JBL sub., Cibie' H4 light upgrade, KC Apollo Pro's, SuperChips Flashcal, Diehard Platinum battery, etc.
98' TJ...gone but not forgotten.