1999 Other GMC Models feul pump

I have a 99 gmc k1500 with a 5.7 or 350 4x4. We just put in a new feul pump but it had a different electrical connector on it. They sad to match wire colors but they were not the same color. Tried many different combos but none worked. Can't tell if we have power to the pump. Could it be a bad relay or something and do you have wiring diagram for pump plugs? Thank you