[JasonACT]

From what I've read, the mk1 doesn't have a CCC, but I can't say if that's "mainly" the difference.

I've worked out the KMs checksum, attached is a Windows exe that may guide you, seems to be producing the results I want for the 3 FG2/X units I own.

I'm starting to think the FPV firmware is different on a FG2, I can see the low-level routines can operate 6 gauges, but I have not found a way to enable the extra 2 within the firmware I have. Same for the 7K vs 8K RPM gauge.

Maybe I shouldn't expect tinkering with an FGX Cluster to allow enabling these options either, it's a different firmware for sure, and FPV were gone baby gone when these were coded.