A flat cut off is OK. Some Japanese units were like that. A kick up to the wrong side is a no-no. I had to fit a Triom unit from a MuZ on the Voxan to get it through a MSVA test, but the tester said a flat cut off would also be OK (a Yamaha TRX850 unit would have worked as the moulding was the same shape but would have needed a relay to switch filaments as the Triom was twin independent beams).
"Do not adjust your mind, there is a fault in the reality"
1957 175 Sport