We should cut this guy some slack, he's obviously new at this guitar modding thing, we were all there once too.
Try a Duncan SSl-5 at the neck (like a Texas Special which kurt had) and a JB or SH-5 P.A.F at the bridge (PAF style humbucker is what kurt originally wanted at the bridge, this one is similar but has more output, better for grunge).
If you want the "best" Duncan pickups for the jagstang in my opinion it would be Seymour Duncan's Antiquity Texas Hot at the neck (which would be like an improved Texas Special, which Kurt had at the neck) and a Seymour Duncan Custom Shop BroBucker at the bridge (this is the ultimate hot sounding PAF).
So you know I made my choices not based on my preference, but on what I thought would get you closest to how Kurt's Jagstang actually sounded as thats probably what you're looking for right?