Outer Limits 4x4 Board

i have a 81 2 door rangie which has front and rear bars, will have a winch up front soon, i'm running a slightly worked 4.4lt with 4spd and 33'' mongrels,and i have been reading on this site about removing the load leveler for increased articulation.
i will be installing a 2'' lift soon and was wondering what springs to use. i was wondering if progressive rate coils from a disco would go well in the rear along with some polyairs as the truck will be used to tow heavy loads sometimes.
i am also wondering what diff upgrades people would recommend as the rear diff only lasted 2 hours off road before punching a gear out the housing!!

thanks
Geoff

Wouldent use progresive rate springs we do a replasement spring to compensate for removing the load leveler and can do a set of springs to suit your winch springs only $360 for 4 you can call 0397396989 and ask for Adrian