Still no brakes

So we have a 2000 Sierra 4x4 in the shop, and have replaced brakes, rotors, calipers, booster and master cylinder, done a brake flush. When the tech was bleeding the he was trying to do it with the truck running, which of course is wrong. So now that we have tried to bleed them manually with the vehicle off, the right way we are getting no pedal still. We have done an abs bleed, manual bleed over and over again. We have vacuum bled and we get fluid out if the rear but nothing in the front. However when we manual bleed we get fluid out the front. Any help would be greatly appreciated.

Abs bleed using a scanner?

If you are able to, drive it and try to make the ABS kick on. Low speed, dirt or gravel road slam on the brakes as hard as you can. The abs should lift the pedal. I know it sounds kinda crazy but that’s what I did with my 2005 and it worked