OK i finally got the car up and running. My problem is with the inline pump.

I have a GST pump in the tank and a Vortech FMU. When I ground the inline pump it starts flowing like 150 psi, even if I'm at idle. As of right now its just sitting in the engine compartment.

My question is how do I regualte its pressure? My car is a 98 with the test port at the end of the rail and I am using a 12-1 Vortech FMU mounted back by the stock FPR and fuel filter.

wow, dude, that stuff all has to come out, the fuel system has to be made to return to the tank. you go from the test port to the in side of the FMU, on the out side of it, you run a line all the way back to the stock FPR, plum it in there, lose the stock FPR completely and then it is allowed to pump in a recuculating method.

The vortech FMU has no adjustment for idle, so you need to keep the stock FPR for idle fuel pressure.

I just needd to know why I am getting that much pressure out of the inline pump.

there is no difference in the idle and boost adjustment, it simply uses the internal diafram and boost pressure for the pressure to rise unless this one is unlike any other FPR I have ever seen. if there is not adjustment and no need for a return line, then there is no way to adjust fuel period. A returnless fuel system only works off pump voltage and a factory regulator, you now have more balls to your pump and to be able to regulate it, it has to return to the tank.