I just purchased another 240sx that had a Pioneer H/U already installed. The factory Clarion amps are still being utilized. The conversion harness uses some resistor looking things (no gain adjustment) to convert the speaker level output to line level for the factory amps to use. I have since removed the pre-installed low end Pioneer H/U and replaced it with my Premier H/U. With the current setup, there quite a bit of electrical noise that can be heard. I assume it's from the use of the ghetto speaker level -> line level conversion. The H/U has front, rear, and sub line level outs. Is it possible to modify the conversion harness and add male RCA's to plug directly into the H/U? Would that work better than a PAC ROEM-NIS2?