1970 Carter AVS, # 4732, on a 383 automatic. I have attached a picture of the idle screw mounting on this carb. The plastic / phenolic piece fits into a hole in the carb and is where the where the screw is inserted. The end of the screw goes all the way through this piece and adjusts the fast ilde. This piece, over time, has broken into 4 pieces. I've tried super glue, but the large end keeps breaking off. That allows the rest of the piece, with the screw inside it, to push back out the front of the hole. This takes away the fast idle since those pieces slide to the front of the car. I may be able to thread the 5/16's hole that these fit into, but I'd like to fix this right. I took these pieces to a local, 30 year carb shop, and he said he's never seen anything like this. I'm trying to find out if this is stock, aftermarket, or some kind of old school fix. Any help would be appreciated, especially where to locate the plastic piece.

Don't know what you got going there with that set up, but here is a stock look.

Then I was mistaken, because that's the screw I am talking about. The red plastic piece fits into the hole from the rear. The problem is that the large ring portion of it, that prevents it from pulling through the hole, broke off. The hole is about 5/16".
I had a carb shop tell me he knows what I'm looking for, but all his cores have a large hole with no plastic piece. Not sure when they did away with this piece and went to making the hole smaller and threading it.

Thanks for the help.

Is this it?

Yes, Sir. That's the animal.

Send me your address & it's yours. Let me know if you only need the plastic sleeve w the nub and the flat plastic squarish washer still on the left side of the screw as those non metallic items can go in an envelope. If you need all I can get a mailer they're cheap

mowch70 can you post pics of your carb with the grommet installed or a broken piece temporarily installed to show where and how it mounts?

I won't be able to until this weekend. However, the picture that Cudaized posted shows a good view. The screw in the forefront of the picture adjusts the idle speed. As you screw it in, it increases the idle by pushing on the piece it makes contact with. Sorry, I don't know the technical name of what that piece is called. On my carb, the red plastic "sleeve" fits into the hole the screw goes into. It looks like on the picture posted that the hole is threaded. On mine, the hole is a lot bigger than the screw, and the sleeve fits into the hole, and the screw goes into the threaded center of the sleeve. The sleeve is pushed into the hole from the rear, allowing the larger part, or shoulder of the sleeve, to fit against the back of the carb casting. This prevents the sleeve from pulling out the front of the hole. The shoulder broke off of mine and the rest of the sleeve, with the screw still inside, slid out of the hole, since there's pressure on it from behind. If you need pics, I'll post them this weekend.

That's the ground terminal, so don't worry about pics, thanks anyways - good to see/know there are some good folks on here still...