77 C10 power brake conversion issues

[77c10]

I recently installed a brake booster and new master cylinder on my truck. It came with manual brakes. I bench bled the master cylinder and installed it on the truck. My issue is the brake pedal goes all the way to the floor now and will not build any pressure. I double checked myself and the pushrod from the booster is attached to the pedal. Is there a difference in a non power pedal and power brake pedal? I plan to take the top off the master cylinder tonight and have my son pump the brakes to see if it is doing anything. Any help or ideas that anyone could give would be greatly appreciated.