I know exactly what you mean, the clocks can be hard to see depending on the weather conditions, I don’t think even with them illuminated it would make that much of a difference.
If anything I’d look at illuminating the speedo needle in a different colour, ( led ).
it makes it stand out more, then possibly run a switched supply to just that bulb holder, I know a few were talking about doing LED bulb sets, but don’t know if it ever left the drawing board !.
If you think ours are bad, try a Peugeot 407, worst clocks I’ve ever seen, illuminated or not.
Late 2000 4.6 vouge, 20" khans, running lpg. Exchange LR engine with low miles.
2.5 dse sold oct 2015
1997 green 4.6 vouge, sold Feb 2014
1997 blue 4.6 vouge, sold June 2013
1992 blue 3.9 classis, gave away 2010
1989 gold 3.5 classic, sold 2006
Etc etc missed out lots, on 14th Range Rover
Nano evo, Thor , dse, EAS kicker..