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I have Fitech and no carb, I finally got around to cleaning up the charcoal canister as I don't have emissions either. I discovered that 2 out of the 3 lines led to nothing...I must have disconnected them at some point, or they were never connected, either way the only thing hooked up to the charcoal canister is the green colored vent line. Does this even need to be hooked up to anything? My understanding is that it originally siphoned fuel vapor from the fill neck using some modicum of manifold pressure? Since this hasn't been hooked up for several years, would pulling the vent line off at the fill neck side and replacing with some kind of breathable filter work? I still think it helps with vapor build up somehow so I am hesitant to just plug the hole. Thoughts? Comments? Am I missing something?

Covered in the TSM. There are some good pictures there.

The green pipe is nylon, which Jeep used for vapor piping in that era. You need a vent from the gas tank, whether that be a vented cap or the fuel tank vapor collection (FTVC). If you have green line, I presume you have FTVC. Not all Jeeps in the '76-77 era had it - look at the table in the TSM. If your Jeep was delivered in California, it's almost certain you have it.

Do you have the canister? Without the canister, you pretty much must use a vented cap. With a vented cap, you should cap the vapor recovery lines to keep from venting into the engine compartment. If you have the canister, I suggest you keep the whole FTVC system. It will vent your tank, not slosh gas out of the filler cap on side-hills, and prevent the gasoline smell that goes along with most old cars - in addition to the clean air advantage. You must use the original air filter with the original canister, since the vapor purge depends on slight vacuum in the "snout" of the air claner. Look at page 4A-18 and 19 in the TSM. Well covered there.