I have a 1991 B250 conversion van who's 318 unfortunately became the perfect spot for a squirrel (possibly a really productive mouse) to create a small nest of crispy leaves and sticks right around the vacuum distribution center. Long story short, it started a small fire and melted a big portion of the wiring harness, some vacuum hoses, and a spark plug wire or two. I'm just getting into cleaning it up and am now in the process of trying to locate replacement parts. I haven't worked on this van much in the past, but my thought was that it would be easier to find an entire wiring harness to replace the existing one than it would be to rewire the small portion that melted. I'm not sure if I'll be able to find the whole thing however.

My question is, what years and engines can I assume had the same wiring harness as this van? I'll also need to locate the electrical switches for the vacuum hoses and somehow figure out where each one was leading to.

Damn squirrel.