"Cliff, you need to re-synchronize the governor with the throttle shaft. Loosen the bolt on the shaft, hold the throttle shaft to wide open and at the same time turn the governor shaft the same direction until it stops, then tighten the clamping bolt back up. This way when the governor will move the throttle as it needs to to adjust the rpm."
If you don't mind asking him why the governor would need to be re-synchronized? Would the small difference in throttle shafts cause this problem? I've disassembled my carb. twice and have never had an idle issue or had to make any adjustments afterwards. Don't take my statement the wrong way as I'm not trying to say he's wrong but I'm just curious for an education sake.