I just did mine, found all sort sorts of varying torque specs on google, not sure if any were actual GM manual specs. I ended up doing about 35 lbs for the pins and although a few sites said to do 32 lb for the banjo-- I chickened out at 20-- felt good and tight and I wasn't about to have to drill out out a busted one!
here's a link I used:
http://torquespecs.tripod.com/s-1xabrakes.htm