The breaking point seems to be close to 1/3 Alcohol.
Less than this and you need constant heat on the glow plug.
But the carbs. seem to be able to meter the fuel.
More than this and you may run into lean conditions.

I would venture to say that a glow style carb. would be better than a gas carb.
at the 50/50 ratio .

Because of the metering Capabilities.

I had asked eariler, maybe on a different thread, if anyone had tried a 50/50 raito on a glow engine.

Perhaps some 20/20 and a little oil added for the bushings.

I got no responce.