the best book to understand, fix and perform with the Q-Jet
https://www.amazon.com/Rebuild-Modify-Rochester-Quadrajet-Carburetors/dp/1932494189/ref=sr_1_1?ie=UTF8&qid=1549920414&sr=8-1&keywords=cliff+ruggles
This guy has rebuilt 40+ engines mostly with Q-jet
He does rebuild them, but has a 6+...