the EJ20G maf only has 4 wires, just like the usdm 1.8, if you look the wires are signal, ground, power, and another wire for the NPS and some read connectors. the only Diff. between the USDM and EJ20G is that the EJ20G provides a power wire from the ECU itself, where the USDM is providing power to the maf thrue a diff. wire. also the shield settup is a little diff. but thats irelevent at this point.
i did not touch any of the MAF wiring, thats still all 1.8. also i hooked up a scan tool, and the readings where accurate coming from the maf sensor. i cant remember the exact messurments, but ill get them again.