Chevrolet Repair: 88 Chevy S10 Blazer-Fuel Pump?, chevy s10 blazer, s10 blazer

Question
My husband has a 1988 Chevy S10 Blazer that will turn over, but not start.  The truck was running fine and I went to start it and it just wouldn't start.  He checked the lines and gas was not coming through from the fuel pump.  He replaced the fuel pump and the relay switch, but it still will not start.  What could the problem be?  Also, is there a specific trick to putting a new fuel pump on and please verify which box is the relay switch for the fuel pump on the driver's side on the wheel well.  We are learning as we go.  Any information would be helpful and very much appreciated.  

Answer
Wow!
First my congratulations on replacing the fuel pump, that is not an easy task for a learning as we go couple.
Second,
Excellent choice on going straight to the relay switch.
Third, lets make sure your relay switch is operational using an ohmmeter. If you need help with this, write back.
4rth does it have throttle body injection. (ie. carberator with a sprayer) or is it fuel injected?