That is unusual... Any chance you kept it? I'd love a few more pic's, anything Victa I have not seen I like to!
I'll pull out the books and see if anything of the sort seems to be apparent, I can see this is one of the set ups for the G2 carburettor, as it was the only one (to my knowledge) that used that sort of Kill Switch, the slide type carby's just asphyxiated the engine, and the G3 and following carby's all had the kill wiring at the carby level.
