PATC has some kits...https://www.transmissioncenter.com/shop/master-kit-a516618-hp-w-front-rear-od-brake-powerpacks-90-02/

But if you want top of the line stuff to handle a lot of HP, I would talk to SMR...http://smrtrans.tripod.com/smrtransmissionsintro/index.html

But definitely get rid of the plastic accumulator piston