I think you should get bigger injectors and junk the FMU. I run 36's with a boost referenced FP regulator. The way it works is for every pound of boost my blower makes the regualtor adds a pound of fuel pressure....a 1:1 ratio. Your set up is really mild so you could probably even get away with 30lb injectors as 42's are way too big and 36's are a little big(I think). I figure that you could get everything that you need for $300 if you find some good deals on ebay or another similar source.
The best price in town right now is from one of our fellow Stangnet members N8Miller. Look it over and drop him a line if you're interested. His AIM screen name is N8playa86.
if your going to take the time and money to change your set do what i did. I got a ford lightning 90mm mass air, 42 lb. injectors, and the harness and connector for the mass air all for 349.00 on EBAY from EMUSTANGPARTS. I had the car SCT tuned on a Mustang Dyno. It drives perfect and the best part is as I add more parts in the future all i pay for is dyno time. with only 6psi my stock longblock vert went 13.2's at 106 but my 60' went from a 1.88 ( NA ) to a 2.08 with the charger.