So Im working on cleaning/ rebuilding my holley 4160 carb this morning, a first for me. Its part number 3310-10. On the metering block there's a plastic piece at the top that I can't find much info about. I took it off when cleaning the metering block and it was a very snug press fit. When I went to put it back together It fell right on. I noticed it was cracked by one of the holes. Can I use this like it is? What is this thing called, what does it do and can I get just a new one? My rebuild kit doesnt have one with. And the meterimg block had a number 10569 in it if thats needed also.