67 Barracuda Dash harness install

Hi, apparently I'm going to need to change out my Dash wiring harness in my 67 Barracuda due to some melted wires down by the bulkhead connector and the bulkhead connector itself. Any tips on what is the best way to go about it? Should I pull the cluster out and try to get the new harness on that and drop that back in as opposed to fishing around underneath? Not looking forward to the under-dash work. Let me know what kind of tips and tricks you guys might have.Not sure how bad of a job this is going to end up being.. thanks