What years front disc brake set up can I use on a 1961 4 dr valiant

the front suspension was different in 60 & 61 and in 62 changed to what is common to our cars.

i'm not sure on the compatibility of the (mainly) lower arms to ball joint & spindle, the uppers look like they'll work. it's probably just figuring out what the ball joint is or the taper is and then seeing what knuckle will work and still perform correctly. so the likely hood of an all factory upgrade is likely fairly small.

however, a disc upgrade using bearing adapter sleeves for the spindle and a plate that mounts the caliper to the knuckle would be fairly straight forward.