My 81 idles at about 13-1500 RPM. I was trying to adjust the idle, but nothing happened when I went up or down, same with the AF screw. Also, the car will randomly just die, and the revs will slowly drop until I stop (with power) when I first start driving sometimes, then when I turn it back on it's fine. Anyone know what's going on? Thanks!

 

Your idle is quite high if your engine is essentially stock.
The most common cause of high idle is a vacuum leak somewhere, which could also explain the mix screws not being very effective.
Other possibilities are a mis-adjusted throttle stop, stuck fast-idle cam/link, and/or a gummed up idle circuit in the carb, or a combination of these, so the car's running on the transition circuit when 'idling'.

You seem to have multiple fuel-system things going on (high idle, but occasional stalls that go away if you shut off momentarily)... I'd start with the basics, like making sure fuel and air filters are clean and clear, checking float-bowl levels through the sight glasses, looking for possible vacuum leaks from bad hoses, etc.

 

Sounds like mostly a vacuum leak to me. The rats nest is full of rubber vac hoses. I'd start by making sure theres no leaks on any connection to the carb.

 

All the hoses that I can see are connected. Also, I looked for the float bowl, I don't see any window or anything like that. I don't know **** about carbs.

 

You not looking for disconnected hoses, thats too easy LOL. I bet some of them are cracked or
not sealing well.

You need to read the FSM, its online here Foxed.ca. Theres carb manuals there as well.

 

One of the most common vac leaks is the questionmark-shaped hose that connects the brake booster hard line to the carb. Being over the exhaust, they get dry and brittle, and engine movement flexes them all the time. I've seen them with actual holes in the underside from age and heat.