I use to have the 440 edelbrock.....sold it several years ago with the notes and instructions, but from memory don't worry about the 0 setting....just adjust to the spot that jets it right....if you don't run out of clicks you won't need another needle. Mine came with another needle but was always able to make minor adjustments in summer and winter to dial it in.....think I was in the high 20's on clicks also. Liked the carb a lot, but it was just killing my thumb to much on long races or all day rides, too stiff for my liking....hope this helps ya.