Year: 1982
Description of problem (please be as in depth as possible):

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Ok, have been having a few issues with ignition recently, and today realised that some of these issues may have been caused by the pretty awful soldering of the wires by a previous owner, as the whole (frayed) wire came out of of the connection plug for the ignition barrel (as seen in the picture).
My question is, how should I go about repairing this? How do you open up the plug to attach the wire back in (once it is repaired)? Obviously I will have to use a different bit of wire because the state of the current one is dreadful; frayed, badly soldered and badly crimped to another bit of wire.
Cheers
Any non-standard parts that might be involved with the problem?
N/a