If you just want to get rid of a few grams to get into the next cheaper shipping bracket there are a few things you can do.
If you are slightly above use the rehearsal packaging service. It only costs you ~$3 and it will reduce the weight significantly, you should always use this service anyways.
If you are still slightly above you can ask for another rehearsal packaging. Tell them your target and have them remove tags and such. They will most likely understand and help you be under the target