I did this, too. First, I got some 6-lug shafts and put them in. Then I used 90's Chevy 4x4 front rotors, which fit perfectly on the ends of the 6-lug shafts. For mounting brackets, I used some front disc brake backing plates. I had the center hole machined out to fit over the 14sf axle tube and drilled 4 1/2" holes to match up with the pattern on the axle's original brake mounting flange. The drum brake backing plate is a great template for this. Then I made some spacers (can't remember exactly, but I think 1.5" thick) to move the backing plates out to position the caliper correctly over the rotor. Then I got some stock 1/2-ton 80's 4x4 front calipers, pins, pads and flex hoses. I made little brackets that mounted with the backing plate bolts that tied the hard lines to the flex lines with the little "index" type thing that the front uses for that connection. I ran new hard lines, but you could reuse your existing ones if they are good. That's about it. I run 15x10 alloy wheels. I posted before about it in more detail if you want to do a search.
You might try using 90's front calipers and pads instead, if they will fit. The 80's ones are a little bigger, so my pads wear funny and I have to grind them a bit every few months.
