Try low 1-1/4 and high 3/4 and I think you’ll find that rich enough for a new rebuild. Your final race setting might be something like 1 turn low 1/2 turn high. Just make sure the fuel tubing connection at the carb doesn’t leak air and don’t take the spark plug out when the engine’s hot.
So most info I’ve read mentions 1/8 on the high and 2 1/2 on the low as a staring point. This is a big difference from what you mention on your earlier post but in fact my sons cadet kart seems to run better with a leaner low and a richer high, leafing me to believe that most motors will run at very different settings. Of so, what is a good way to find the specific setting for my sons kart. Another statement I’ve read is that these motors should be running around 450 CHT, I am lucky if I see 390CHT. Any info on this would be great.