Slartibartfast - Good to see an update on your build thread.
Sorry I can't help with the technical questions.
However, at some point I need to get my car noise tested at Goodwood.
I seem to recall that you are based close (ish) to the circuit.
So, if you were interested, perhaps we could arrange to meet up?
I haven't arranged a date yet, so it is just a thought at this point.
Cheers, Paul.