Auto Parts: 1998 Isuzu Rodeo Instrument panel wiring

Question
I own a 1998 Isuzu Rodeo and the speedometer went bad. bought a 2004 model instrument panel to replace it but the wring harnesses are different-they don't fit. I have the new wiring harnesses with the new instrument panel and would like to hard wire it in, but the color coding seems to be different as all the wires do not have a match, even though the amount 40 of wires is the same. how can I figure out how to match the wiring and should it work? thank you

Answer
    You'll have to get a wiring diagram for both trucks and sit down and figure out what is what.  Most public libraries carry the repair books with the diagrams in their reference section, believe it or not.  I have used this resource several times when I could not otherwise obtain a diagram or was just in a hurry.