91 f250 radio install confusion

[diesellaxer]

As the title says I have a 91 f250 and am having some issues with it. The wire colors are not the same as on the wire harness for my radio.

The colors on the harness for the truck are:
White/Green
Orange/Green
Black/White x2 (there are two of these)
Yellow/Black
Black
Green/Yellow
Orange/Black
Blue/Red
Red

On the radio the colors are:
Black
Red
Yellow
White
white/Black
Grey
Grey/black
Green
Green/black
Purple
Purple/Black

Now here is the thing...blue/red and red were not used previously.

Yellow/black- plugged yellow from radio into it
Black-Plugged Black from radio into it ....both turns on the radio when plugged in.

Green/Yellow
Orange/Black....both of these supply power, I plugged the red from the radio into them and it turned on the lights to the radio

Now if you do the math, there are more wires from the radio to the truck.

Anyone know or have a wiring schematic I can use thanks!