You got to look at your car, the FSM and TSBs.
from the MTSC it looks like 72 uses a manifold collecting the tank vents and then a line to the cannister.
1970
Heated Air Intake and "Vapor Saver" (Session 271) from the Master Technician's Service Conference
1972-3
1973 Imperial and Chrysler Clean Air System Reference Service Repair Book from the Master Technician's Service Conference (Session 302)
The link Diymirage posted prob has more info.
The charcoal cannistor isn't that hard to open and replace stuff.
You can probably do a simplified version. The one on my '85 Grand Wagoneer was/is a bit of a pain 'cause it uses an unavailable electric solenoid on the carb vent and a two stage purge on the cannister.
