rb26/s14 wiring/plug identfy

[rbpowerds14]

hi,
well i had my wiring harness done by stephen at swapwiring.com, and well lets say its a big cluster fuck! i had many problems getn my car running due to the wiring being incorrect.
i finally got it to work but now the harness is just a big mess. im in the process of redoining it(shorting wires to the proper lenght,not 5 ft longer then needed) also rewrapping the harness to clean up the engine bay.
i need some help identifing a plug. it was never used nor nothing plugged into it. i need to know can i just eliminate it from the harness or is it need and what connects to it. location- on rb26 harness right where the plastic cover starts(covers the wires going by the fuel rail
picture

(the plug on the bottom,)

2nd thing im going to be running the greddy emanage ult. with this setup. im opting to use the map sensor instead of the stock mafs. my question is since the greddy map sensor comes with its own harness that plugs into the emange unit itself can i just remove the orignal maf wiring from the harness, like depin it from the ecu? or is it needed for something eles?
thank you