Technical Engine Smog Lines

When pulling a motor out of a seventies smogger to be swapped into a fifties car, should the assorted tubes that went to the carbon cannister be blocked off or left open. I'm guessing they are vacuum lines and need capping.
Dick J

 

if you're really clever, you'll put the canister into the old car, and not have that gas smell every time you park it.

But yeah, plugging them is a good plan. One is probably a vent on the carb (that would be a larger hose, near the top of the carb). The small one(s) would be vacuum.