I have a 87 k5 Silverado that I am trying to put a new fuel pump in. I have brand new tank, straps and a spectra premium module and hanger assembly. The problem is the pump assemby has a quick connect clip and the original wiring is...just wires. The ground cable I can identify and can figure out, the other wires in the quick connect and original wiring are different colors. What is the best method to identify which goes to which? Also I believe that once I ID the wires, I can cut the quick connect and do a splice and crimp. I am I wrong in this thought?

 

The best way to figure out the wire colors/function is to find a wire diagram for that particular vehicle. I believe my gm pump instructions gives me that info for my blazer.

I wouldn't splice and crimp. They need to be soldered and covered with heat shrink. If you insist on crimping I would only use a closed end style connector. Twist the wires together, fill the connector with RTV, shove the wires into it then make the crimp. This gives the best defense from the crimp getting corroded.