Okay, so you want to use manual CSC rather than automatic CSC or fast blanking mode.
If you need me to generate CSC coefficients, it could be several weeks before I am able to complete this.
Here are the assumptions I will make:
IN_A will be ADC0/G/AIN4
IN_B will be ADC1/R/AIN6
IN_C will be ADC2/B/AIN5
OUT_A will be Y
OUT_B will be Cr
OUT_C will be Cb.
-Matt