69 Dart Custom Slant Six carb help needed!
The 6260 was a service replacement carburetor offered by Holley for '70-'72 198 and 225 engines. That number is carb's only ID number; there was no metal tag with additional numbers or info (Carter carbs had their ID number on such a tag).
Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted
here for free download.