Line up the holes on the drive shaft with the holes on the differential input flange. The hole pattern is a rectangular pattern--not a square! If you can't get the bolts in one way, index the drive shaft 90 degrees and try again.
Make sure you put a washer on the under side of the head of the bolt and one under the head of the cool jet nut.
You will need a 9/16 wrench and a 7/16 wrench to tighten up the bolts.
Bring ALL of the bolts up snug and then tighten them all. We torque them to 25-28 foot pounds.