The math setup should use your wideband AFR and the commanded AFR to get a % error.
Does your car have a stock wideband? I see log numbers that look your wideband in the parameters as "MPVI2.1 -> PLX" and again as "MPVI2.2 -> PLX", but when I search for that name to use in Maths - User formula, I can't find it.
Do you have an MPVI2 Pro? Are you getting your wideband info thru the CAN bus, or thru a serial port, or one of the extra MPVI2 Pro channels? (I use serial, as 2006 didn't have CAN bus)
In this image I tried "ID 31070 PLX iMFD - Eq Ratio [external input]" hoping that that was your wideband, but no, it didn't populate.
My wideband Maths-User looks like this:
That %error can be plotted with the same axis as the MAF table (as in the image above), or the Main VE table, or your fuel injector table... basically any table.
Once the %error is plotted (graphed) the same as your Main VE table, you can apply it (paste special, multiply by %) or multiply by half %.