The 99 does have the metric wheel pattern. I havent seen or herd of any one making a hub to go to metric (just the other way around). The only thing that I know would wheel adapters from like a dapt it usa wheel adapters. Maybe someone else might know of something else. Good luck
DRW= Dual, Rear, Wheel. You would have to replace the hubs to a SRW(Single Rear Wheel) or run H1 wheels in stock form. New hubs are around $180-new each. Its driver side diff. Other than that it will work great.