All you need to do is remove R135.
When I modify some P05 ecus I would sometimes get a solid Cruise control light when using an Ex cluster. Or a solid Upshift Light when using a Cx/Vx cluster. So I went in and found that the cruise and upshift light use the same pin on the ecu D18. So i followed the traces and it lead to the R135 resistor. I removed that resistor and bam, Cruise/Upshift light gone.