What are you thinking of by "fuse box", exactly? The big one under the hood is integrated with the engine room main harness, I believe. Do you just need to replace some of the outer plastic parts? There are a few replaceable modules making it up, but other than those, replacing it and not the whole harness would involve a whole lot of terminal removal and replacement, or a whole lot of splicing. The one under the instrument panel might be more modular. I think the harness connectors plug into it. I think it's combined with the body ECU.
