40 amp ign fuse pops when i turn the key


My 1997 montero sr has a short in the wire harness. I think its the wire between my neutral position saftey switch and the wire to my starter. I inspected the wireharness closely from the ignition, through the fender, and under the car where i could, but i could not find any exposed or damaged wire, so i took it to a budget (90/hr) mechanic.

from what i can tell the mechanic linked the 40 amp fuse ( the modified fuse was still in there) this melted the wire near the ignition switch ( its melted now and was not before). WHen i spoke with him picking up the car he told me he was sorry, there was melted wires, he left the covers off so i could see them, i need to replace the wire harrness in the cap and the engine bay, but he could not fix the car/ the price would not make since for the value of the car.

Has anyone ever replaced the wire harness in the cab or the engine bay? How many pieces is it in? Im going to call the dealership tomorrow to get a price quote but maybe someone has advice?