I would first ask what you are trying to correct with the needle adjustment? The needle adjustment is not going to effect the mix at WOT or idle, it just effects the mix in the mid throttle range.
If you motor runs and burns perfect at WOT but is rich or lean in mid throttle that's when you need to do a needle adjustment, if your motor isn't perfect at WOT then you should be working on WOT tuning instead of the needle. Tuning at WOT is done by adjusting the air flow (due to air filter and exhaust), adjusting the jet size, or adjusting the float setting. With the CNS carb I recommend you first make sure you have a high flow air filter (not the plastic one with the foam insert) and then do a float adjustment (lower fuel level in the bowl if your WOT mix is rich, raise the fuel level in the bowl if your WOT mix is lean). If the above doesn't correct the condition at WOT then you might think about adjusting the jet size. AFTER the motor is running just right at WOT is the time you would worry about the needle setting.....
