Baba this is a problem that seem to comes up quite regularly.
Thanks to an idea from fellow 'bolter Dan Bowles I fitted my New Vintage Woodward series gauges using his technique.
Like Project Helen says,there are billet adapters available but at a price.....
Assuming your old original gauges are kaput and you don't mind cutting them up you can use the original shells as housings.
Here's how I did mine.
Retro-fit gauge installation.

I'm really pleased with the end result.

I hope this helps.



1950 Chevy Advance Design 3100 in Scotland
In the Stovebolt Gallery
More pix on Flickr.
I've definately got this truck thing in my blood ... my DNA sequence has torque settings
"Of all the small nations of this earth,perhaps only the ancient Greeks surpass the Scots in their contribution to mankind" Winston Churchill.