No. The 55 lbs. refers to the amount of fuel it delivers per hour.
The stock fuel pressure regulator is not adjustable. If you have the correct add in tune in the computer and the proper size injectors, you don't need to adjust the fuel pressure.
+1 typically the MAF will be calibrated with the injector size. so if you are running the stock ECU you will need a MAF that is calibrated for the 55lb injectors you plan on using. Now that will change if you plan on having the car tuned at a dyno shop, ask them what they recommend you to buy.. some tuners are more comfortable with one item over another.