You can switch to a master cylinder for disc brakes - on a 1st gen like my 1980, it would be a starquest - bolts right onto the booster. 2nd gen probably a montero. The reason to change it is the calipers need more fluid than the wheel cylinders. The starquest master has a 1" bore, the truck is a 7/8" bore. I will be doing a rear swap with a rear from a 95 2nd gen Montero - its a 9" rear with discs and I got the suspension links and the panhard rod with the driveshaft for 200. Just need to find better gears for the rear - it comes with 4.625s and expects 31-33" tires - stock 1st gen are 26".