What would it cost to replace the main wiring harness on a 2005 Rubicon?

There are issues with it. Melted wiring in spots. Looking at replacing actually while I have the opportunity.

Thanks,
Jack
As far as I know you're going to have to go the used route. Ebay, junk yards, deadjeep.com, etc. If I were you, I'd just removed, inspect, repair, and reinstall.
 
I had to replace mine in 2012. Jeep will not sell you one. I waited in queue for months before they fessed up. That was irritating because my TJR was only 8 years old at that point. Not much support there.

I sourced a used harness from Daveys Jeeps for I think $500. Anyway, you'll be doing either used or custom. Expect to pay a lot more than $250.