Did you get the head running to your satisfaction yet? One thing that you will need if you get the Metrolux II timer is the probe. That is installed in the head and will keep the output constant by variying the time according to the output. Very handy. At www. you can see the new light sources that work with VC papers. I believe that the light source now recommended is V45. Pretty straight forward to install. Don't know the price. Keeps you from having to loose the exposure speed when the 40 yellow is installed.\