OK I've finally got the time to have a go.
Here's the procedure I followed:
1. Convert each image to greyscale in PS CS3 and save.
2. Open each image in Registax V4, and apply 'Dennis wavelets" (1=20.1, 2=10.5, gaussian linear) and save.
3. Load each image into CS PS3 again and combine into RGB.
4. Levels (top slider each channel down to 192).
5. Curves (I chose standard increase contrast curve and then lifted the dark end of the curve a bit).
6. Selective colour: Cyan -60, Magenta +40, Yellow -32, Black 0.
7. Save for the web.
The wavelets might be a bit harsh for this image - it looks a little grainy to me when combined to RGB.
Thoughts?
Al.