So I've now removed the B&M connector from the outside shell so I can trace the wires from pins 8 and 24 back (picture 1).
They lead to a coax cable that has been spliced to fit in the connector, reducing the alot of the EMI shielding effects provided by the coax (but that's just me being anal!)
I used these tap wire splice connectors that cut into wire and provide an additional connection to that signal (picture 2).
When I probed the signals, there was a lot more high frequency noise than before so it was difficult to detect any change in the signal amplitude.
Unfortunately, this scope does not have any real time filtering I could used but it does allow FFT so I can analysis the frequency response in (sort of) real time.
Picture 3 shows the signal along with the frequency response.
To prove the Mic was still behaving as normal I tapped the light cluster to look for any spikes at the low end of the frequency response.
Thankfully, it was showing a change when ever I tapped the light cluster or made a loud noise (with some delay) so I think I'm just going to go for and make a cable.
Wish me luck!