Anyone ever re-wire a 4 banger harness to work with V8?

Doesn't seem so since I get "Sorry - no matches. Please try some different terms." everytime I try and search on the subject here.

But has anyone done this yet? The guy from my local Ford Dealer said they don't sell the harness anymore (M-12071-C302). I am thinking I can do this or at the very least use the 1987 truck harness and modify that to fit and add the MAFS later like the 1987- guys do...

Also if you got some diagrams to show, please do so. I got a Haynes manual but more info won't hurt me.

UPDATE: I found the 25 page EFI book from Ford Motorsports, so I will use that as a base to work with, doesn't look very complicated too. I found another dealership SVT that has the wire harness in stock, it's true that Ford doesn't make them anymore. They go for retail $370 CAD but I dealt it down to $325... I am waiting 2 weeks before buying anything so I can get the best deal possible.