Do you have an all-out racecar? If not then there's no reason to use a slotted rotor. They use up pads quickly. Every time you push the brakes the rotor cuts the pads like shredding cheese. The cross-drilling.. nice but causes stress fractures, which leads to needing new rotors quicker, too.
I think for the price, you'd be better off finding a blazer's spindles & dual-piston setup & swapping them on.