well i can answer that one for you. I do electronics for a living and learned early that glass fuses tend to oxidize as well as the contacts in the fuse box. This ends up causing a high resistance connection between the fuse and the fuse holder. As we all know resistance equals heat and the fuses will heat up to the point that the solder melts. To fix this problem replace the fuses with new ones and burnish the fuse contacts with a barrel brush for cleaning a rifle (the metallic kind). I'm not sure what caliber works best for this, the one I had was laying around in a junk box. This should take care of the hot fuses. Althogh a short or large current draw would cause this too, in theory it should cause the fuse to melt as long as the fuses have not been replaced with larger ones. I hope this helps you, the ultimate fix would be to replace the fuse panel with an ATC blade type but of course that means rewireing.
