I've just thought of a wicked idea.
I can't change all of the dial faces, but I
can change the centre one. Notice how small the gap is between the bottom of the needle and the bottom of the dial? There can be a tiny slit there which you'll never notice, which is how you can slip the new face on.
The beauty of this? I only have to print a singular face - the colour face on transparent paper. As I'll be re-creating the face using the scans of the original, I just need the block colour printed on a transparent sheet.
Like this:
Keeping all original holes, so slipping it over the original face would then look like this:
And because I have spare faces, I can keep testing until I get a perfect fit. Once it's done, pop open the dials (easiest thing in the world to do), slip the new one over the old, and job done!
Some more colours:
So yeah, going to try that ASAP! Will scan in the dials tomorrow and should be able to print them by this weekend!
If this works, I'll have the template for re-creating these for anyone - a very easy upgrade!