HUD/Digital speedo control unit? where is it?

[duey]

*91 240SX SE coupe*

Well i guess i'm part of the "digital speedo don't work" club, but today since i had some free time i decided to try and fix it. I took the whole digi speedo assembly out and reflowed EVERYSINGLE resistor/chip/diode/etc on it and it still doesn't work. So now i'm pretty pissed cuz i spent over 5hours reflowing every soldered point on the whole thing.

Now once i put everything back together i noticed that i have 2 plugs under my dash that are not connected to anything. One of them runs along the harness with the cruise control/dimmer switch/headlight control buttons.... it is plug with 4 wires, and it's sitting there doing nothing..is that the control unit that i'm looking for?

Also the second unknown plug is about 8-12 wires on it and it is coming off the harness where there are plugs going into the door harness, i doubt that this is what i'm looking for but if anyone knows....what the heck does this plug goto? I don't think it's too important because i have no check engine light on and the car runs fine.

Thanks to anyone who can help.

-duey