help me sort out Dimmer & Illumination !

I have a question regarding the wiring of my headunit (Alpine CDA-7995) to the wiring harness of a 1995 Volvo 850 Turbo. I dont understand how to utilize the "ILLUMINATION" function of the headunit, or if its possible.

The orange wire from the H/U is expecting a +12V connection. The closest i can find on my harness chart (see below) is a Rheostat+ (10a) & a Rheostat- (11a). The Rheostat is a "slide dial" on the dash which allows you to lower the intensity of the interior lighting.

Will hooking up to the (+) of the Rheostat work for me? what do i connect to the (-), just to ground? Am i "S.Outta Luck" on the dimmer/illumination?

if i cannot use this, then what do i do to these wires? should i just cap then off individually? will a break in the circuit affect other lights in the dash panel?

here is a legend for the wiring of the harness. (The end of the harness has 2 plugs which connects to the OEM stereo, labeled "A" & "B") :

1A = Dash Left Speaker +    red / white

2A = Dash Left Speaker –    yellow / white3A = Antenna +    blue / white4A = Battery + 12V    red / black5A = Not used 6A = Ground    black7A = Dash Right Speaker +    yellow / green8A = Dash Right Speaker –    green9A = Not used 10A = Rheostat +    pink11A = Rheostat Ground    black12A = Battery + 12V    red / black13A = ACC +    yellow / violet14A = Ground    black 1B = Left Rear Speaker –    brown / black2B = Left Rear Speaker +    brown / white3B = Left Front Door Speaker –    green / brown4B = Left Front Door Speaker +    green / white5B = Right Rear Speaker –    pink / black6B = Right Rear Speaker +    pink / white7B = Not used 8B = Not used 9B = Right Front Door Speaker –    red / black10B = Right Front Door Speaker +   red / white

another question(s)...why does the "A" plug have (2) Battery +12v (4a & 12a)? & why are there (2) Grounds (6a & 14a)?

if the pink wire is controlled by the dial you have, then this is the wire you hook up to the orange of your radio. You don't need to hook up the negative of this switch. Just cap it and see what happens when you turn on your dash lights and try to dim it. It should work. Make sure you get the correct ground wire for the headunit.My Personal Installer Note: Connectors are easy, neat, and professional. But do you know how to crimp properly?