Here is a thread over on Pirate that talks about it.
https://www.pirate4x4.com/forum/general-4x4-discussion/2246754-jk-dana-44-wj-brakes.html . There is a slight advantage to using the WJ brakes over the JK brakes, since they are slightly bigger, but as others have said, it is probably easier to just get a whole JK setup, knuckles and all.
JK front caliper piston 2.6" (66mm) dia. or 5.31 in^2 (area)
WJ front caliper piston 1.889" (48mm) dia. or 2.805 in^2 (area) times two = 5.61 in^2 (area)
JK front rotor 302mm dia.
WJ front rotor 305mm dia.
JK front rotor swept area 220.6 in^2
WJ front rotor swept area 255 in^2
JK master cylinder bore diameter 1.0"
WJ master cylinder bore diameter 1.0"
So the magic is in the 15% larger swept area of the front rotors and a slight hydraulic leverage ratio increase. The WJ must have a taller brake pad that covers a wider section of the rotor radius since the diameters are almost identical.