The wiring you show is fine, having caused a spark I would have a look at the fuses, as you may have popped a fuse, usually on pre engaged starters such as yours the solenoid is arranged so that the lower 13mm connection is a little bit of braided wire that goes into the starter motor body, the other 13mm nut then holds the battery and alt wires, with the 1 remianing being direct from the ignition switch, they don't usually use a relay on the solenoid side of the sw, but I can't say for def on yours, just that they don't normally, normally a black/blue wire.
tabetha