Final Drive
 

I'm about to purchase a set of Final Drive
the question is
I currently have a JDM B16 Tranny with LSD
and my plan is change to 4.9
the F/D now should be 4.4
do I require any parts other than the shaft and the Final Gear
I heard from changing a 4.4 to a 4.9
it requires 1st gear, distance collar and needle bearing
so the package from 4.4 to 4.9 should includes 5 different things?
correct me if i'm wrong
thx