Carter YF 3211 automatic choke

I have a 1956 Chevy 235 P/U with a manual choke, and am looking to replace this with a Carter YF 3211 with automatic hot air choke. Where is the best place to vent hot air from to the carb (I've never set one of these up before). Thanks

 

stock exhaust manifolds had a small tube through them that the tube from the carb connected to. Wrap about 1 turn of copper tube around the exhaust manifold ,the other end connects to the carb.

 

thanks for the help