Great progress again. Do you have tyres yet? Or hub caps? Wheel nuts can be had from Mike Dowley of course.
I have re-lettered several panels - its a bit fiddly and the results depend very much on the panel being rust-free with clearly stamped lettering. It is simply a matter of getting a small pot of Humbrol enamel (I prefer ivory - not white - doesn't look so new). Then paint it over the letters and then lightly wipe it off with a cloth. If you end up with a slight smear over the surface, you can let it dry and then polish it off with a mild abrasive like Solvol. The same technique can be used for the lettering on the top ingnition advance/retard clamp, the slow running and mixture controls, and the Lucas lettering on the original horn push if you have it.
Here's the Bed-Pan's panel: