Ok, the whole picture...
The new EI red cube sensors are functionally the same as the FloScans, except their K-factors are in the 60,000 range instead of the 30,000 range.
The dual fuel flow setup is an optional configuration that can be used by anyone that has a return fuel line and has a second fuel flow sensor to feed it. This a new capability unique to SkyView, customers with an EMS need to use the external Matronics computer. If you're not using the 2nd input, the pul/gal setting (K-factor) for the second set of pins is irrelevant and can be ignored because it won't be seeing any pulses anyway. So it's always subtracting "zero" from your single sensor.
The tag on your FloScan says 16-XXXX. To come up with the pul/gal number, add a zero to XXXX to make it XXXX0. That's ends up being a number between 29000 and 31000 usually - each sensor is individually calibrated by FloScan. Use that number as the pul/gal setting on the first fuel flow input (pin 14). If anything is connected to pin 19 (sounds like not in your case), it's always subtracted.
Hope that clears it up!