The 7800 Juansolo posted showed previously is mine.
The only thing from the LHE on this is the automatic CMOS switching on the 2 chroma signals, but used a CD4066, so maybe that has more isolation as its 4 single pole switches, rather than the double pole in the LHE. Needed to generate an inverted signal to toggle the 2600 chroma line. Didnt even know the LHE did the switching, until I looked at schematic after I added this to mine today.
With the chroma disconnected from the motherboard at the pin, theres still that diagonal interference on a PAL 7800, its got 2 sources of it.
Theres another oscillator circuit for the PAL colourburst, which cannot be total isolated from the PAL clock input pin on the MARIA. Theres a output on the TIA that seems to keep it running.
I totally disconnected this oscillator circuit from the MARIA, and its now running its own tin can PAL crystal oscillator. The interference is gone.
The BAT85 diode on the Magic Knight board really helps the luma balance between the 7800 and 2600 side.
Heres a close up of Ballblazer, looks fantastic.