info on mass air conversion

As the new year begins i will make my speed density 86 to a mass air, I have the air processor module, jumper wire harness, sensors, hoses and clamps.
Everything that comes with the kit. But i don't know if i need anything else that the kit does not provide. Maybe another sensor or some kind of wire(s) that will help out during the process? Any info would help me out.
Also, does the mass air help out with adding horse power, or just help run the car better?