8.25 from. 97+ will have 29 spline shafts versus the 27 spline in earlier models.
And you will want the driveshaft with the 8.25 because the pinion is longer on that axle so the driveshaft is shorter slightly.
So many people to thank here's a start to the list
Spidertrax, Yukon, rustys, warn, branik, PSC, advance adapters, Bad wheels, interco, essentially off-road. And many more
Most of all thanks too Ian Johnson and the xtreme off-road crew for all their work, and 4 wheel to heal for their part in it too.