This Holley carb is not mine but I came across it on the local Craigslist. The seller appears to knowledgable as he recommends Drew P for the rebuild. And scores bonus points for listing the numbers on the metering blocks so the buyer is informed.
https://cosprings.craigslist.org/pts/d/colorado-springs-1968-ford-shelby/7694898573.html
That carburetor is for a KR. Not a GT500.
Pat
Wonder why it hasn't sold?
There is a good chance the carb is sold. Notice it was posted 2 months ago. It is more likely the seller has not removed the listing. That is a good price.
Cory