I don't know. I did determine that the fuse holder I used was actually the version rated at 20A (based on the AWG) - I must have swapped out the 20A for a 30A fuse, so maybe the combined draw of all the consumers off the switch was just too much, it definitely overheated.
So, I've re-wired the Ignition switch feed (from Shunt) via the Midi fuse block. Using a 40A fuse to match the value of the fusible link previously replaced with the inline blade that melted.
Sectioned the supply plate
Approx 3mm wga Red/Blue to match original ignition switch feed (Red-White) from shunt to 40A fuse
MTA Midi fuses & power supply crimp terminals
Replaced (White) feed wire from fuse block to Shunt, approx 3.5mm wga Brown - mine looked iffy. Sliced it open to look at where the wiring was kinked. Actually in better shape than the insulation appeared. I had bought some 7.8mm Female spades of the type used on the Datsun, thankfully.
Used 60A Midi fuse - original link was 80a, according to chart. Feed line from main fuse block is 80A
labelled so I don't forget what feeds what (have to figure out what the 3rd one is for)
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