With the hundreds and hundreds of these engines that are running just fine out of the box, I struggle believing there's an inherent design problem. I do think that the string Jim's referencing above does point out a potential problem regarding our OP's issue. There's a good chance the spring tension or lever height in this carb is incorrect, forcing the LS needle to be open that far. That leaves some options.
1. Just run it. If there are no issues and the engine handles OK, we're good.
2. Some may try to adjust the lever/pop off pressure to bring the low speed needle setting back to normal, but knowing exactly how tedious this job can be, this option is not going to be for everyone.
3. Buy a new carb. They aren't that expensive.
-Al