A body Front Disc brakes.

Here is the kit I am investigating at the moment. It doesn't allow you to keep 14" stock rims or 4" (small stock bolt), but its a pretty good upgrade from stock.

Right Stuff Detailing MDC46DCZ - Right Stuff Detailing 4-Wheel Disc Brake Conversion Power Kits. It can be found only at 2 locations, Right stuff Detailing .com or Summit, Summit is cheaper.