posi rearend question??

[Bigo Serge]

Hey fellas,
Im working on my 6.0 swap (will post a build thread very soon) I am rebuilding the rearend and changing from one wheel peeler to a factory posi carrier with 373 gear. I was wanting some input on replacing the old clutches and springs with new ones. Does anyone know who sells them or if they even need to be replaced? I plan on using my original axles, replacing the bearings, crush sleeve, seals, and gasket. Thanks in advance