ok seeing as I got no help on this ill share what I learned this week for the future. The disc brake diff has different axle tubes and brake set ups can not be swapped from disc to drum and vise versa, however the guts and axles are the same. The yoke on the pinion was different as the donor truck had an aluminum drive shaft and had smaller u-joint. I did not change the proportioning valve and hence the brakes are a little softer due to the excess volume needed for the larger rear calipers, I didnt change the valve cause the electric plug was a different size on the 2000 donor truck. The brakes are still stopping the truck ok but will deffinatly be looking into finding a valve that does cross over. Also there is an e-brake cable length issue. We discovered that the spider pin has quite a bit of play inside the carrier and believe this is why the pin snapped in my original diff. I will be taking it a little easier on this diff as cool as the two wheel smoke shows are. anyway hope this info can give a little knowledge for the future. when i find a proportioning valve that crosses over i will post what one.
