I need more torque and locked differential. Options?

[Ezgohunter1]

First the cart, a 97 DCS converted to 48V with 8V Powertrons. ScottyB hooked me up with 2 ga cables and Alltrax DCX 400 controller. It has a Jakes 6" spindle lift with 22" tires and HD springs all the way around. The motor and differential are stock. I built this into a hunting cart and today was my first trip up the mountain. It has some pretty steep inclines and my cart was spinning a lot on the passenger side. I could transfer my weight over the passenger tire and it did not spin. The plowman and buggies unlimited posi units are for 98 and up carts. Is my 97 differential different , and if so, what are my best options for positive traction? I would also like to increase the torque of the cart and would like to know the cheapest option for this? Thanks in advance for suggestions.