Where would I have to attach the vacuumed line from? I was thinking between the carb and engine, on the manifold its self where the brake vacuumed line takes off? Or is that not correct?

Can't give you a specific on the carbed motor's but i is definitely a manifold mount and probably by it self is best.

It does need to go into the manifold runners, best keep it away from the servo pipe. As the manifold will have no common area to get an acurate reading link 2 cylinders togther for a more stable suction.