Time to remove and repair, possibly replace, under dash harness

If you can solder, and get a couple of crimpers you can rebuild it. It is a fair amount of work. Having a bench large enough to "stake" it down and stretch it out with nails helps A LOT. Lay it out, tie it and nail it down, and temporarily tape/ tie off each branch and strip the wrappings off.

You can buy most of the terminals.

It really just depends on how much money you have vs how much time and skill you have