Plumbing a radiator overflow?

The Pontiac ('56 Star Chief) has been puking out a little antifreeze after I park it. Gonna add a catch jar, but wondering how the internals of the reservoir should be plumbed. Does it need to be vented? Does the "in" tubing need to reach near the bottom of the tank to suck coolant back up? As for placement, does the tank need to be any certain level below or even with antifreeze in the radiator?
Thanks!
Johnny

 

A catch can? or recovery tank? They are not the same.

A recovery tank would be best but you would need the correct rad cap to go with it.
Recovery tank will have the hose go to the bottom of the tank and covered with water. Yes it will need to be vented. You want the recovery tank as close to level with the top of the rad as possible. The lower the tank the less efficient it will be.

 

What kind of capacity should I shoot for and what is the difference in the rad caps?