What you have there is commonly known as a "Frankencab" It's a one of a kind custom built unit and there will be no schematics for it.
So it's just you and your Tim the Tool Man belt versus the Frankencab. Even if you got it working I dont see much money in it.
That thing is one ugly son of a bitch Just sell it as is and be happy with every dollar over fifty you get from that heap.