Hello, rebuilding another 904, this one is from a 1970 challenger that im gonna put in my dart. Ive done a few stock rebuilds on mopar and ford transmissions so thats no issue. Im planning on doing some upgrades, billet rear servo, hd kickdown band strut, red alto frictions and kolene steels, shift kit and so on. But I've been told that I should possibly upgrade the planets to steel versions if I have the aluminum ones. What parts are required for this? Just the planets? Or do I need anything else like the ring gears? Any thrust washers?