For the FHM to do much good at all they need time to reproduce. Stock them as early as you can preferrably with little to no predator pressure.
Will the 2-3" bass immediately be a predator threat to those minnows or will it take a little more growth from the bass?
Also, what about the bluegill? If the minnows get wiped out, will the bluegill provide forage for the bass without decimating the bluegill population in the process?
