If I was doing it myself I would do in this order of importance depending on finances.
1-beast sun shell
2-corvette servo or billet servo (billet servo only with appropriate wide re-enforced band)
3-udated 3-4 clutch set (z-pack) (raybestos stage 1) (borg warner performance set)
4-Borgwarner 29 element dual cage input sprag
5-Transgo HD2 kit
6-OEM not aftermarket 5 pinion planets front and rear.
Hope this helps but when building bear in mind there is far more to building a strong reliable unit than just throwing good parts at it.
Frank at PerformaBuilt
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