short circuit fuse problem

[85raiderburban]

driving down the freeway, she lost all power (no head/tailights, no instrument/gauges power, no cd deck). There is no switch 12v power either. turn key to acc position and it acts as if battery cables are disconnected.
only the aftermarket cig lighter used for usb adapter has power (since its hooked to constant 12v).The radio and gauges/instrument fuses were blown. BUT the yellow wire (pictured) I had from the orange (ign switch 12v) going to the engine side of the firewall powering a seconary junction block specifcally for inline electric fuel pump, 4L80 +12v, LED fog lamps and trans cooler fan.
For some reason the fuse didnt pop but instead when all this occured but MELTED. Has anyone had this happen before??? And why do i have no power? the starter wire is tight. if i have to i will remove and rewire fuse box and external plug to get this back up and running