Volvo Repair: 1989 volvo 740 gl radio and dash board and gas mileage, volvo 740 gl, wire colors

Question
Ummm i i bought my car and there was no radio so me and my uncle tried to put it and we did it then it go stolen and now i don't know how we hooked it up. please tell what wires hook to my cd player the wire colors to my car are as follows: green w/ red line,green w/ grey line, white blue orange yellow black. me and my uncle cant figure out what dashboard wont light up when all the bulbs are good and it has juice going to it it just wont light up. my car has 215,914 miles and i only get maybe a 275 to 300 miles to a tank  of  gas and i thought since it was a four cylinder it would be great on gas. please help me?

thanks James  

Answer
James, thats all you get with Volvos.  22-25 on the highway.  They arent the best in Fuel economy.  I hope you have a test light to test the wires.  Those wires all sound like speaker wire colors.  Test them with a 9v battery.  Turn the dimmer switch on the instrument cluster.  It might be turned all the way down.  Roger