who did the Tune and build up of the engine? As always, start with the cheap stuff first
. Retunes foir performance issues are usually free from the tuner. if the car is running good with out any bucking or missing, it may not be the tune. Are you positive SHM sent you the right parts? Maybe do a compression check first, that would alteast tell you if you are getting any blow by or any cylinders arent up to snuff.
With the power you SHOULD make, yes maybe larger injectors and a bigger fuel pump would be wise. There is no reason to pay that much on parts, then to skimp on something as important to an engine as fuel.