I have a 1990 Laredo. I put a new fuel pump assembly in and now I have no fuel pressure. This is the third new assembly I have put in. I have power to the pump and can hear it prime up. My problem was getting air in the fuel system. have new filter and now another new pump but no pressure. Myself and the three other auto techs in my shop can not understand what is going on. Please help

 

I am not familiar with the '90 model. Where is the regulator located? I think I would be looking at that.

 

Silly to mention, but how much gas is in it? Air? Orientation? IIRC the second line on the pump plate ends up at about 2:00.

 

Check for something simple like DFlintstone is suggesting. The larger diameter line is the fuel feed line that goes to the fuel filter. Any chance you have the return and feed lines swapped? Also, is the fuel filter in the right orientation (fuel flow in direction of arrow). The regulator is on the rail and you should be getting good pressure with a new pump right at prime. It should also hold pressure once the pump stops (without the engine running).
When you changed the pump, was there a lot of rust in the fuel screen?