On the carb, some have an electric solenoid for the vent and it's on the top front of the carb, a bigger hose, it should lead across driver side to under the fenderwell inner where the charcoal canister is. All that can come off and block the vent, I went inside it to remove the rubber poppet valve (about $2K in hospital charges there for me at the time!!!!) to then vent the carb internally and more externally IIRC. Look close for a possible power valve external vacuum hose, most likely does not have it but if you remove that if present the car will not run under power because the power valve will not work. Most '79-'80s don't have it, only the ones that were about to go to full feedback carb had the set up. You need one vacuum line off either the full time or spark ported tube on carb to provide the distributor vacuum advance. It often goes to a ported vacuum switch mounted low on the engine block or the outer driver part of the intake. You can plug that off simply running the vacuum line from carb to distributor. Any rubber line coming from fuel tank to the charcoal canister is a vent of sorts, if plugged the tank may need it for venting especially if the fuel cap is not a two way vented one. Later fuel caps vent to vacuum only and not pressure for emissions, no telling what's on the car presently. If the heating controls are all cable you can pretty much drop all other lines, it may be convenient to keep the vacuum set up to the air cleaner intake that controls preheat air for cold weather operation, that can make the engine run better when stone cold in winter. The flipside is it then heats the intake air up more, you give up a slight amount of power there, the cold air intake thing.
If automatic trans you'll need a vacuum line to the modulator on it or trans won't shift right.
Just so you know, emissions equipment is federally not state regulated, the fines can come from there too but who's watching eh? Just a FYI.