First off, my car is a Canadian 85 LG4 (so there's no computer)

My warm idle is around 1000 in park and 750 in drive. This causes a clunk from park to drive and too fast of a rolling speed for what I like. I see on my emissions sticker it says that the idle should be 550~500 in drive, however when I set it that low it is prone to stalling. If I don't warm it up for at least 10 min before putting it in drive, it stalls even on a warm day. I have the choke properly set and it does it's job but when I kick it down it still is too cold for the 550 idle and it will stall if I'm not on the gas. If I do sit there and take 15 min to warm it up all the way to operating temp it does fine. Stumbles a bit sometimes coming to a stop but it never stalls once it's warm

I set the idle mixture screws using a vacuum gauge and also checked my timing, so I'm not sure what's causing it.

 

500-550 sounds really low. I have my 350 carb-swapped '83 Z set to idle at about 675 when in gear.

I wouldn't want it any lower than that, personally. If it were me I'd turn yours up a little bit to at least 650 when in drive.

 

Where does it idle in neutral? Mine seems to rev up too high when I take it out of drive

 

Somewhere in the neighborhood of 750 or so, if I recall correctly, but I know for sure it's at 675 in drive.

 

Hmm, that sounds about right to me. When mine is around 650 in drive it is nearly 1000 in park! Any idea why mine revs so much higher than yours in park? Doesn't really make sense to me

 

Mmk, manual or electric choke?

Verify that your choke is all the way open when it's in park.

Once that is taken care of, try unhooking the throttle cable and seeing if that makes it go down (maybe it's hanging ever so slightly or something).