Heh. I didn't read that carefully either.
a. Thought was looking for a CO2 meter ...
b. A Proform carb means that its likely the transfer slot is long or wide, the idle feed restricion is above fuel level and there's an extra 'emulsion hole'. (There have been enough of Proforms measured and posted on RFS forum to expect this is so).
Therefore establishing the correct transfer slot relationship may be more difficult. To go further in improving the carb performance, especially the "idle circuit", will require measuring and fixing these things. Once the restrictions and bleeds get outside of a certain range the fluid dynamics become erratic and less consistant. The "idle circuit" has a big influence on fuel milage especially below 55- 65 mph....