Polk PA D1000.1 Remote Bass Knob HELP

OK so here's the deal. i bought a used PA D1000.1 amp and the guy did not have the bass knob. It is for a boat install so I really want the knob. Called Polk and they were very helpful and offered to ship me one for free. Here is where the issue comes in, They do not have stock of the original knob for that amp. They sent me the knob and cable for the PA D880, which has a 3.5mm mini headphone end on it. The PA D1000.1 requires a phone looking connection. I called again and they sent me the phone type cable, but no knob to go with it. I'm fine with cutting the two cables (3.5MM end and the phone cable) and fabricating, but the 3.5mm cable with the knob attached only has 2 wires in it ( a black and a red), where the phone type cable has what looks to be 6 wires. Polk support says they do not have a wiring diagram for the 1000.1 knob. From what I have seen, it looks as if maybe the 1000.1 knob might have possibly had a light on it, and maybe some of the wires were used for this? All I need to know is just what wires on the 6 wire phone cable to match up with the black and red on the other cable to get this thing to work. Can anybody assist? Or is there any other generic knob that can be used? I believe they have ones that go in line with the input RCA cables, but will this truly accomplish the same goal? Thanks so much for your help.