After a discussion with Ed, one of my other Jag building customers, we arrived at ''what colour should he paint the Jag''?
After a bit of searching I came across this reference chart from a company that does restoration and rebuilds of all manner of exotic and classic vehicles.
The PDF below is the chart information, however if you go to the site for Team CJ (link at the bottom of this post), you can view examples of the colours as well.
All credit to Team CJ In Austin Texas, USA for the chart.
https://classicjaguar.com/archive/paintcodes.html