Not exactly sure what tube you are talking about, just can't picture it. I might have one. As for installing the later pulse air injection here in Cali, no go, not original equipment, you have to have the air pump system. Might be able to use the later air injection tube/manifold set up as long as you maintain the rest of the air injection pump system. I will warm you though that the smog Nazis here in Cali will fail it for not being "original equipment" even though it does the same job. I know, I ran that on my '83 and ended up having to source a mani and log that was proper for an '83.
Most confusing thing is how the air injection BBQed the carb. Can't see that happening unless you had a fuel leak or maybe using an aftermarket air cleaner assy. that would allow a lot of fuel vapor to congregate in the area of the leaking air injection tube.
Where are you located? Town wise, Maybe someone close could give a hand. I frequent Fresno and San Luis Obispo areas.