Update on FMU problem: Resolved!

[FoxFour]

Sorry if I haven't posted in a while; my father passed away on Feb 27. About 4 weeks prior I had a friend install my Vortech SQ series supercharger in my Mustang Cobra. Since the car was completed I got the reprogrammed computer back but the darn thing detonates at around 5000 rpm. Without a fuel pressure and boost/ vacuum gauge I just decided to drive it easily till I could narrow down what the problem is.
Just installed the gauges last weekend and herein lies the problem. When boost kicks in the FMU doesn't. It has an 8:1 ratio FMU, meaning that for every 1 pound of boost, the FMU should increase fuel pressure 8 psi. Fuel pressure stays at 42 psi no matter what, that's normal WOT pressure. I checked the inlet and return line that connects to the FMU and they are not reversed, checked and made sure that the FMU was not damaged by checking it with a pressure/vacuum hand pump, pressure spikes up when applyng pressure to it while engine is idle, like over 100 psi, so that works. Vortech guy said to check the line that goes to the FMU and make sure that no other line is connected to it, may be messing up the vac signal that way, there was a line running from the diverter valve so I rerouted that and ran a single line from the FMU to the fuel pressure regulator like the manual says, still nothing!
Then I ran the line to another vac source-Nada still!! WTF!! I am running out of vac sources under the hood. I am trying not spend more money by ditching the FMU and getting the 'puter tuned with new injectors and mass air but if I have checked everything properly, this should not be happening. I was looking at my Ford service manual cd, I may try another stronger vac source, even my mechanic friend is scratching his head on this one, he said that he will be coming over Sunday to look at it and see if he can come up with any ideas.