That's how I've done it, 4 injector wires --> 4 black resistor wires --> 1 red resistor wire --> 4 twisted-together deadplug wires.
Wiring them incorrectly really won't affect the afr's much. They'll open a tad quicker, but generally their extra latency makes DSM's too lean. Regardless, in my experience no injector scales juuuust right vs OEM. You have to play with battery offsets or dead time/latency to get it idling right, then you adjust the rest of your map via scalar. Many other EMS's require this, but usually they use ass-backwards names like some Nissan apps.
If you know the injectors are goofy, you spilt the difference by adjusting idle partially with the scalar, partially with the offset. This is so the rest of your map isn't off much. Generally not the ideal way to do it.