Your current drum brake MC will not support the disc brake calipers fluid needs. You really need to get a disc/drum MC.
But then you need upper control arms, new bushing and ball joints and brake lines too. After you buy all the small parts you'llhave over $300 in to the F/J/M swap.Jim_Lusk said:It's extremely easy to find rotors and calipers for the F/M/J spindles. And, it will cost you less, to.