It's many years since I used Cibachrome or Ilfochrome but when I did I used two bath black and white developer to control the contrast for I found making unsharp masks somewhat tedious. I used Selectol Soft and Dektol and divided the time in each developer equally for the test strip. When I dried and assessed the test strip I could judge whether the times were OK and adjust as neccessary. It's about 12 years since I last made prints using this method and they are still OK with no sign of fading or deterioration. I was told by a number of colour printers that they would not be permanent. I also used regular black and white fixer but had to use the Cibachrome bleach. It proved to be considerably less expensive than using the Ciba chemistry.