I kept thinking about the reply to Nick from Smiths Guages and wondered why, if the problem is heat generated by the bulbs, they dont use LEDs on these instruments as they do on more modern designs. I realise they also mention the mechanism as well but surely it is worth a try. I searched on the internet and I found this site that offers LED replacement bulbs for instruments. Croll down a bit to find them.

http://www.norbsa02.freeuk.com/goffyleds.htm

I don't know what style of bulb the Morgan instruments use but this site seems to offer a good range.

Peter

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