from what i read on scca, you need a LX booster/master cylinder and resevoir, the block thing that the line goes into and splits and some skill with bending brake line. the lx block has 4 outlets and you only need 3 for a s/c cuz the back runs off one line, not two so you plug the unused hole. the trickiest part i guess is cutting/bending the lines in the engine compartment to fit on the lx one. i will try to find the page for you.
1991 Super Coupe -
Performance=5.0 H.O. w/M5R2 5speed, 3.27 gears w/CF TracLoc,95 Cobra intake, 75mm Power throttle body, fenderwell CAI, C&L 73mm mass air w/24# injectors, FRPP E-Cam,Trickflow spring kit & Crane 1.7 roller rockers on stock E7s, MAC shorty headers, Flowmaster cat back w/hiflow cats, MSD plugs, coil, wires, electric cooling fan, 190lph Walbro fuel pump, BBK pulleys, and a B&M shifter. Drilled/slotted rotors, power brake conversion, Tokico Blues, Eibach springs, tons of poly, T4MO ecm