Wiring HELLP!!!!

Ok, engine out all new core plugs fitted now all back together but I have an issue with the wiring.
If if switch ignition on the black relay next to coolant reservoir clicks but I get no buzz from the fuel pump.
Trying to start it up, the brown/orange wire from positive on battery to main wiring loom burns up.
Im really stuck now need to get car back on the road today can anyone help??

Edit, wire burns up without even going to turn it over, just switching ignition on!!!

Is the engine earth connected/good condition?

Sorted glow plug wire was shorting on the head