Charging System Problem---Fuse Box

[hiryux]

To start off somehow my battery won't charge properly. At first it seemed like the battery. Got that replaced four times. Then I changed the alternator and it still wont charge the battery. Later on I smelled something electrical burning under my hood and found it to be located to where the positive terminal cable was. It seems that the red harness with one of the two plugs in them are really hot and it kinda melted the red plastic on the harness. The cables lead to the fuse box. My question is the cable something replacable or do I need to get the whole fuse box with cable? Is it something I can buy at my local autoparts store or at a dealer? Did anyone else run into this kind of problem? Any input is much appreciated. Below should be a picture of the red harness I was talking about. Thanks in advance.