[ROVERNET - UK] Jaeger clockface

[Alan Gale]

All this talk of gauges prompts me to ask if anyone knows tips on 
cleaning the faces of old car clocks?
I pulled the clock out of the Rover 10 because it was not working and 
was thinking watchmakers when i thought maybe a shake and she'll kick off.
and she did.  perfect time.
however the face has some surface rust spots (It looks like it has spent 
a bit of time open to the atmosphere). does anyone know any tips for 
cleaning the faces without destroying the lettering and artwork?
Or are there some neat replicas anywhere?

Alan Gale