Stuck on defrost

Found 2 bad vacuum lines. Took it to mechanic. Decided to try fixing it myself. 2 days later I looked under hood and mechanic had removed both lines. Darn! I think I found heat resistant line that will fit.
But I can only find 3 connectors to attach 2 lines to.
Both missing lines connected one end to a bigger line (comes from down low passenger side of motor, by generator) sticking up with a plastic T connector for two more lines. Those two nipples are easy to find. The 3rd place I found missing a line comes from a short line with a dual adapter just 8 inches or so from the firewall, on passenger side, under hood. One of the two from this dual adapter is missing a line, the one that IS there is stiff and goes almost straight and downward towards under the wiper fluid, this one looks fine. Those are the 3 places that I can see to connect 2 lines. Can you please tell me how to find the 4th place to connect line? The dual adapter I mentioned, I can't find where other end of line would go?
I have ramps.
Thank you, thank you, thank you!