No horn, hazzards or AC

Greetings,
300tdi defender 110, ROW spec.

Whilst trying to start up for the first time after replacing the head gasket I saw smoke creeping up from under the bonnet when I held the key at the heater position. Upon inspection the glowplug wire chain was partially melted mainly at glow plugs # 2&3.

Checked the wiring to see if the metal parts of the connectors were touching the head at any point and they were not. I replaced glowplugs #2&3 since I had doubts about the quality and condition. The 100Amp fuse under the driver seat for the glow plug circuit blew as well. I have used the landy for about 2 weeks since then (without aid of the plugs since I have hot replaced the blown 100A fuse as yet).
Here is where it gets a little confusing:
Currently my horn, hazzard lights, AC blower are not working and I am unable to flash high beam by pulling the stalk on the steering column in the back position.
Indicators, low and high beam work as normal.
I replaced the 20 amp fuse for the AC blower circuit and it blew immediately upon turning the key in ignition to the first notch.

I would like to think the glow plug issue would be separate and unrelated to the other issues but I have come not to believe in coincidences.

Where do you think is a good place to start troubleshooting? My gut tells me ignition switch...

Id say some of the wiring has melted insulation causing shorts. Pull the binicle off and check behind and from ign. switch as you say.

Have you checked the fuse box?
You may have blown a few fuses

Just closing this one out. Sorted.

Issue appeared to be associated with one of the glow plugs. Three plugs confirmed as having good resistance whereas one was measuring as open circuited.
Bought new glow plug loom and a new 100A fusible link. The original loom had melted pretty badly in addition to Reinstalled the 4 plugs with new loom leaving the faulty plug disconnected until I can replace it.
I spent days/weeks investigating the landy's electrics. I would never have imagined that a shorted glow plug circuit would have prevented my hazzard lights, horn, AC fan and the headlight flash function from working.