Lawson, reading your earlier post prompted me to invest in the gadget suggested above by Teknome.
bought off eBay as a just in case purchase, it does exactly what you'd expect and is quite straightforward to use.
This is the item I bought (no other connection)
https://www.ebay.co.uk/itm/Range-Rover-Classic-TVR-Morgan-Lucas-14CUX-hotwire-diagnostic-cable-kit/224011772032?hash=item3428246080:g:3-cAAOSw6qpa157K
Gary
